ÔN TẬP CHƯƠNG 1_ĐẠI SỐ 8

Đa thức${\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}}^{\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">49</span></span></span></span>}$x^2-49 $$x^2-49$$ được phân tích thành nhân tử là:

• $<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">7</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">7</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$\left(x-7\right)\left(x+7\right) $$\left(x-7\right)\left(x+7\right)$$

• $<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">7</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">7</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$\left(x+7\right)\left(x+7\right) $$\left(x+7\right)\left(x+7\right)$$

• $<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">7</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">7</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$\left(-x-7\right)\left(x+7\right) $$\left(-x-7\right)\left(x+7\right)$$

• $\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">7</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$x\trái(x-7\phải) $$x\left(x-7\right)$$

Chọn câu trả lời đúng. Kết quả phân tích đa thức${\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}}^{\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">y</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">y</span></span></span></span>}$x^2-5x+xy-5y $$x^2-5x+xy-5y$$ thành nhân tử là>

• $<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">y</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$\left(x+5\right)\left(xy\right) $$\left(x+5\right)\left(x-y\right)$$

• $<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">y</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$\left(x-5\right)\left(xy\right) $$\left(x-5\right)\left(x-y\right)$$

• $<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">y</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$\left(x-5\right)\left(x+y\right) $$\left(x-5\right)\left(x+y\right)$$

• $<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">y</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$\left(x+5\right)\left(-x+y\right) $$\left(x+5\right)\left(-x+y\right)$$

Kết quả phân tích đa thức$\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}{\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}}^{\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">3</span></span></span></span>}}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">20</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}$5x^3-20x $$5x^3-20x$$ thành nhân tử là:

• $\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>}^{\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}}$5x\trái(x-2\phải)^2 $$5x{\left(x-2\right)}^2$$

• $\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>}^{\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}}$x\trái(5x-2\phải)^2 $$x{\left(5x-2\right)}^2$$

• $\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">2</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$5x\trái(x+2\phải)\trái(x-2\phải) $$5x\left(x+2\right)\left(x-2\right)$$

• $\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">5</span></span></span></span>}\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">+</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">4</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span><span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">(</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">x</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">-</span></span></span></span>\mathrm{<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">4</span></span></span></span>}<span\; class="katex-container"\; data-idx="0"\; contenteditable="false"><span\; class="katex-display"><span\; class="katex"><span\; class="katex-mathml">)</span></span></span></span>$5x\trái(x+4\phải)\trái(x-4\phải) $$5x\left(x+4\right)\left(x-4\right)$$