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Help two questions only!!!!

Help two questions only!!!!-example-1
User Nullforce
by
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1 Answer

5 votes

Answer:

1)
9^(2)=81

2)
7=log_(2)(128)

Explanation:

1)

We need to use the property of power and logarithms, particularly this:


a=x^{log_(x)(a)} (1)

So, let's take take the exponent:


9^{log_(9)}((1)/(81))=9^(-2)


(1)/(81)=9^(-2)

now, we can write the negavitve power as:


(1)/(81)=(1)/(9^(2))

So, the aswer will be:


9^(2)=81

2)

Applying equation 1, let's take log in base 2 on each side of the equation


log_(2)(2^(7))=log_(2)(128)

using the power definition in log, we have:


7log_(2)(2)=log_(2)(128)

Therefore, the answer is:


7=log_(2)(128)

I hope it helps you!

User Mr Washington
by
6.1k points