Question 125082: I have looked around and can not figure out how to solve these....this needs to be factored:
16x^4-81
Thanks in advance. Answer by bucky(2189) (Show Source):
You can put this solution on YOUR website! To solve this problem you need to make use of the factor form:
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which says that the difference between two squares is equal to the product of two binomials that
are formed by the difference and the sum of the square roots of the two squares.
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Suppose you let A represent Then A^2 would be and this is equal
to
.
In addition we can say that
.
If we substitute those two values into the factor form we get the difference of two squares
on the left side, so the factored form is the right side and it consists of:
.
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Then notice that also fits the factor form because it can be written as
the difference of two squares in the factor form as follows:
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.
Substitute this factored form for and the whole thread of factoring
results in:
.
.
And that is the answer to your problem. Hope that you can track this OK. It's a little bit
difficult to explain.
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