# I need help simplifying ...

• Jan 15th 2008, 08:56 AM
XIII13Thirteen
I need help simplifying ...
Help me simplify ...

$sqrt{90(2x-3y)^6}$
• Jan 15th 2008, 09:22 AM
TKHunny
Use parentheses to clarify meaning.

Do you mean this: $\sqrt{90*(2x-3y)^6}$?

Hints:

90 = 9*10

$(2x-3y)^{6}\;=\;[(2x-3y)^{3}]^{2}$

Let's see what you get.
• Jan 15th 2008, 10:12 AM
XIII13Thirteen
Quote:

Originally Posted by TKHunny
Use parentheses to clarify meaning.

Do you mean this: $\sqrt{90*(2x-3y)^6}$?

Hints:

90 = 9*10

$(2x-3y)^{6}\;=\;[(2x-3y)^{3}]^{2}$

Let's see what you get.

Thank you. I only just joined the forums today. I've tried to get the math text functions down as best I could. The function I was trying to write appears as you have typed it. I'll take your hints and see what I can do with them.
• Jan 15th 2008, 10:17 AM
XIII13Thirteen
I'm getting $(3x-4y)^3$

Is that correct? I multiplied the 90 into the equations making 180x-240y to 3x-4y
• Jan 15th 2008, 10:31 AM
topsquark
Quote:

Originally Posted by XIII13Thirteen
I'm getting $(3x-4y)^3$

Is that correct? I multiplied the 90 into the equations making 180x-240y to 3x-4y

Not quite. Think of it this way:
$\sqrt{90(3x - 4y)^6} = \sqrt{90} \cdot \sqrt{(3x - 4y)^6}$

What does $\sqrt{90}$ simplify to?

-Dan
• Jan 15th 2008, 03:19 PM
XIII13Thirteen
Quote:

Originally Posted by topsquark
Not quite. Think of it this way:
$\sqrt{90(3x - 4y)^6} = \sqrt{90} \cdot \sqrt{(3x - 4y)^6}$

What does $\sqrt{90}$ simplify to?

-Dan

$3\sqrt{10}$
• Jan 15th 2008, 06:58 PM
XIII13Thirteen
So is it

$3\sqrt{10} * [(2x-3y)^{3}]^{2}$ ?
• Jan 15th 2008, 09:37 PM
topsquark
Quote:

Originally Posted by XIII13Thirteen
So is it

$3\sqrt{10} * [(2x-3y)^{3}]^{2}$ ?

$3\sqrt{10} \cdot (2x - 3y)^3$
$3\sqrt{10} \cdot \sqrt{[(2x - 3y)^3]^2}$