Answer:
Step-by-step explanation:
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Using power rule we get that
Evaluating this at gives us: .
We could write without negative exponent giving us:
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We could also go about it an algebraic way.
Notice the numerator is a difference of squares and can be factored as .
We need a factor in the numerator to be so we can get rid of the on bottom and then substitute for .
Recall the difference of cubes formula:
We are going to use this on the denominator:
So that first factor there will actually cancel with a factor I mentioned for the numerator earlier.
Let's see it all together:
After the cancellation we have:
Now we are ready to replace with .
We have some like terms to combine: