Algebra 2 - Where does the imaginary unit i come from, y = x^2 + 4

The video tutorial covers graph transformations, specifically shifting a graph upward by 4 units. It then explores solving quadratic equations using the square root method, highlighting the challenge of taking the square root of negative numbers. This leads to an introduction to imaginary numbers, explaining the concept of the imaginary unit 'i', which represents the square root of -1.

What happens to the graph of a quadratic function when a constant is added to it?

• It shifts downwards.

• It shifts upwards.

• It shifts to the right.

• It shifts to the left.

Which method is used to solve the equation 0 = x^2 + 4?

• Factoring

• Graphing

• Square root method

• Completing the square

Why can't we take the square root of a negative number in real numbers?

• It results in an undefined number.

• It results in a complex number.

• It results in a positive number.

• It results in zero.

What does the imaginary unit 'i' represent?

• The square root of 2

• The square root of 0

• The square root of -1

• The square root of 1

What is the result of the expression ± sqrt(4) * sqrt(-1)?

• ± 4

• ± 2

• ± 4i

• ± 2i