Simplify use only positive exponents in your final answers

(-3x^2y)^3 (-3x^-3y)^2

(5a^-1b^2)^-2 / 125a^5b^-3

(8x^6y^-3)^1/3 / (2xy)^3

Any help would be greatly appreciated

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- Apr 23rd 2008, 02:21 PMTH1Need Help Exponents Due Tomorow
Simplify use only positive exponents in your final answers

(-3x^2y)^3 (-3x^-3y)^2

(5a^-1b^2)^-2 / 125a^5b^-3

(8x^6y^-3)^1/3 / (2xy)^3

Any help would be greatly appreciated - Apr 23rd 2008, 02:23 PMMathstud28
- Apr 23rd 2008, 02:29 PMTH1
No since the variable y isn't suppose to be an exponent but I meant everything else

- Apr 23rd 2008, 02:35 PMMathstud28
I will show you all the tools then

YOU apply them

It will help you learn

$\displaystyle (ab)^{n}=a^{n}\cdot{b^{n}}$

$\displaystyle a^b\cdot{a^c}=a^{b+c}$

$\displaystyle \frac{1}{a^b}=a^{-b}$

using this last definition in conjunction with the second one we can see that

$\displaystyle \frac{a^c}{a^b}=a^c\cdot{a^{-b}}=a^{c-b}$

$\displaystyle \sqrt[c]{a}=a^{\frac{1}{c}}$

Apply those..not all are used...it is up to you to figure it out...if you have any specific problems post them and we will help

Good luck - Apr 23rd 2008, 02:37 PMMoo
Hello,

Applying the formulas : $\displaystyle (a^b)^c=a^{bc}$ and $\displaystyle a^b a^c=a^{b+c}$

You should get the answers.

$\displaystyle (-3x^2 y)^3 (-3x^{-3} y)^2=(-3)^3 x^6 y^3 (-3)^2 x^{-6} y^2$

$\displaystyle =(-3)^5 x^{6-6} y^5=(-3)^5 y^5=(-3y)^5$

Can you calculate the followings ? - Apr 23rd 2008, 02:40 PMTH1
Would the final answer be 243y^5 and what about the rest of the other questions

- Apr 23rd 2008, 02:42 PMMoo
There's a - sign missing...

It would be exactly the same method for the followings.. - Apr 23rd 2008, 03:14 PMTH1
For the last one how would you do that one since the exponent is a fraction and for the second one would the answer be 25a^3b

- Apr 23rd 2008, 03:27 PMMathstud28
- Apr 23rd 2008, 04:08 PMTH1
I dont understand what you wrote since for the last one the exponent is 1/3 and I dont know what to do for that part

- Apr 23rd 2008, 04:10 PMMathstud28
- Apr 23rd 2008, 04:18 PMMathstud28
See if this helps

http://www.mathhelpforum.com/math-he...tml#post134788 - Apr 23rd 2008, 04:30 PMTH1
For the exponent 1/3 i know you have to evaluate it but when you evaluate it on 8 would it be 8/3 or would you simplify 8 as a power of 2^3 and the answer be 2 since the 3 cancels out

2^3 1/3 - Apr 23rd 2008, 04:33 PMMathstud28
- Apr 23rd 2008, 04:40 PMTH1
Thanks I have another question

if x=1/2 evaluate the expression (-2x^-2)^3(6x)^2/ 2(-3x^-1)^3

I have evaluated part of it without substituting x=1/2 and I have

(-8x^-6)(36x^2)/ 2(-27x^-3) so what do I do from there