Learn how to rewrite an expression when taking the square root of a negative number

The video tutorial explains how to rewrite expressions using the imaginary unit I. It begins with an introduction to the concept of replacing the square root of negative numbers with I. The tutorial provides an example of rewriting the square root of -9 by breaking it down into components and using properties of radicals to simplify the expression. The video concludes with a summary of the process, emphasizing the use of the imaginary unit I to simplify expressions.

What is the imaginary unit 'i' used to represent?

• The square root of 1

• The square root of -1

• The square root of 0

• The square root of any positive number

How can the square root of -9 be rewritten using the imaginary unit 'i'?

• 3i

• 9i

• i9

• i3

What is the result of simplifying 4 times the square root of -9 using 'i'?

• 3i

• 9i

• 12i

• 12

Which of the following is a property of radicals used in the simplification process?

• Radicals can be divided by any number

• Radicals can be added directly

• Radicals can be split into separate square roots

• Radicals can be multiplied by any number

What is the final simplified form of 4 times the square root of -9?

• 4i

• 12

• 12i

• 9