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

Postby orange1998 » Fri Mar 30, 2012 10:42 pm

(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(: :wave:

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

Postby maggiemagnet » Sat Mar 31, 2012 10:44 am

orange1998 wrote:(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.

orange1998 wrote:(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.

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

Postby orange1998 » Sun Apr 01, 2012 5:02 pm

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. :) :) :D

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

Postby maggiemagnet » Mon Apr 02, 2012 12:41 am

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