Add and Subtract Complex Numbers

Front

What is a complex number?

Back

A complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is the imaginary unit, defined as i^2 = -1.

Tags

CCSS.HSN.CN.A.1

Front

How do you add two complex numbers?

Back

To add two complex numbers, add their real parts and their imaginary parts separately. For example, (a + bi) + (c + di) = (a + c) + (b + d)i.

Tags

CCSS.HSN.CN.A.2

Front

How do you subtract two complex numbers?

Back

To subtract two complex numbers, subtract their real parts and their imaginary parts separately. For example, (a + bi) - (c + di) = (a - c) + (b - d)i.

Tags

CCSS.HSN.CN.A.2

Front

What is the result of (1 + 2i) + (3 + 4i)?

Back

The result is (1 + 3) + (2 + 4)i = 4 + 6i.

Tags

CCSS.HSN.CN.A.2

Front

What is the result of (5 - 3i) - (2 + 4i)?

Back

The result is (5 - 2) + (-3 - 4)i = 3 - 7i.

Tags

CCSS.HSN.CN.A.2

Front

What is the conjugate of a complex number?

Back

The conjugate of a complex number a + bi is a - bi. It reflects the number across the real axis in the complex plane.

Tags

CCSS.HSN.CN.A.3

Front

How do you simplify (2 + 3i) + (4 - 2i)?

Back

Combine the real parts and the imaginary parts: (2 + 4) + (3 - 2)i = 6 + 1i.

Tags

CCSS.HSN.CN.A.2

Front

What is the result of (6 + 2i) - (3 + 5i)?

Back

The result is (6 - 3) + (2 - 5)i = 3 - 3i.

Tags

CCSS.HSN.CN.A.2

Front

What is the result of (4 - 7i) - (-3 + 6i)?

Back

The result is (4 + 3) + (-7 - 6)i = 7 - 13i.

Tags

CCSS.HSN.CN.A.2

Front

How do you add (1 + 5i) and (1 - 5i)?

Back

The result is (1 + 1) + (5 - 5)i = 2 + 0i = 2.

Tags

CCSS.HSN.CN.A.2