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Which expression is equivalent to (1)/(2^(-2)*3^(-2)) ?

Which expression is equivalent to (1)/(2^(-2)*3^(-2)) ?-example-1
User RexSplode
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2 Answers

19 votes
19 votes

Answer:

B Description is in the picture

Which expression is equivalent to (1)/(2^(-2)*3^(-2)) ?-example-1
User Igor Danchenko
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3.1k points
10 votes
10 votes

Answer:


2^2*3^2

Explanation:

By definition of a negative exponent:
((a)/(b))^(-x)=((b)/(a))^x=(b^x)/(a^x)

In the last step I simply distributed the exponent, but this actually goes both ways! So we can do:
(b^x)/(a^x)\implies((b)/(a))^x

The next thing you need to know is that:
(ab)^x=a^x*b^x

and like the previous statement, it works both ways! So this means:
a^x*b^x\implies (ab)^x

So the denominator of the expression given can be expressed as:


(2^(-2)*3^(-2))\implies (2*3)^(-2)

Lastly you need to understand:
1^x just simplifies to one, because
1*1*1*1...\text{ x amount of times} will stay equal to one. So we can thing of 1 as being raised to some number, even if not explicitly stated.

This helps because we can write one as:
1^(-2)

so now we have the expression:

(1^(-2))/((3*2)^(-2))

Well this can because now we can "factor" out this exponent just like how it was demonstrated in the beginning

We get the expression:
((1)/(3*2))^(-2)

Now we use the definition of a negative exponent, to get the reciprocal giving us the expression


((3*2)/(1))^(2)

We can now "distribute" this exponent across the division to get


((3*2)^2)/(1^2)

Well 1 squared just simplifies to 1, so it's redundant to write.

This gives us the expression:

(3*2)^2

and as stated before we can distribute this across multiplication, and another way to think of it is:


(3*2)^2\implies (3^2*2^2)\\\\\\text{because } (3*2)^2\implies (3*2)*(3*2)\implies(3*3)*(2*2)

we're just grouping the like terms, so we can write them as an exponent.

So this gives us our final expression:

3^2*2^2

or


2^2*3^2

which is the option B, since the order in which we multiply does not matter.

User Davio
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2.4k points