Question

Find the exact value of the radical expression in simplest form.
the square root of 16 times y cubed − the square root of y cubed

3 times y times the square root of y

3 times y squared times the square root of y

4 times y squared times the square root of y

4 times y times the square root of y

Answer 1

@JimmyC @phi ???

Answer 2

How many times do I have to tell you to not ask for math. I'm taking summer school for math right now :P

Answer 3

@JimmyC sorry lol

Answer 4

First, write out the problem in "math"
\[ \sqrt{16 y^3} - \sqrt{y^3} \]

look for "pairs" inside the square root, and then use the rule
\[ \sqrt{ x\cdot x} = x \sqrt{1} = x \]

also, remember the little number in the upper right means multiply by itself that many times.

The idea is : write numbers as factor of prime numbers and write out the letters to a power in expanded form. then look for pairs:

\[ \sqrt{16 y^3} - \sqrt{y^3} \\ \sqrt{2\cdot 2 \cdot 2 \cdot 2 \cdot y\cdot y\cdot y}- \sqrt{y\cdot y\cdot y} \]

can you do the next step: pull out pairs?

Answer 5

you pull out the y^3? all of them?

Answer 6

only pairs. anything left over stays inside the square root.

and when you pull out a pair you put only one of the pair on the outside