## Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4

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orange1998
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### Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4

(3^2x)(9^x)= ?
Does it, or does it not, equal 27^3x

Another...

(a^2)^b (a^b)^2 = a^4b Correct?

Also..

a^-4/b^-4 = (b/a)^-4 That's incorrect, right? Shouldn't it be (b/a)^4 a positive exponent, not a negative?

Thanksssssssss(:

maggiemagnet
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### Re: Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4

(3^2x)(9^x)= ?
Does it, or does it not, equal 27^3x
No, it doesn't. Try turning everything into powers on 3, and see what that does.
(a^2)^b (a^b)^2 = a^4b Correct?
If you mean (a^2)^b * (a^b)^2 = a^(2b) * a^(2b) = a^(2b + 2b) = a^(4b), then yes, this is correct.
a^-4/b^-4 = (b/a)^-4 That's incorrect, right? Shouldn't it be (b/a)^4 a positive exponent, not a negative?
Mathematically, they're the same, but books and teachers always want "with positive exponents only", so (b/a)^4 is the "right" way.

orange1998
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Joined: Tue Mar 27, 2012 5:51 am
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### Re: Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4

What do you mean try turning everything into power on 3? I'm confused on that one.. The rest still make sense and I'm good on, thanks.

maggiemagnet
Posts: 358
Joined: Mon Dec 08, 2008 12:32 am
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### Re: Exponents: (3^2x)(9^x), (a^2)^b (a^b)^2, a^-4/b^-4

Turn 9 into a power of 3. Then use the exponent rules.