How do you factor $2c^2-32d^2$ ?

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Answer 1 · 2017-03-12T21:47:27

$2(c-4d)(c+4d)$

Worth remembering the standard form of $(a^2-b^2)=(a-b)(a+b)$

IT CROPS UP ALL OVER THE PLACE

We have a version of it in this question!
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So we look for values that we can square

2 is a problem so lets try and 'sort of' move it out of the way

Factor out 2 giving:

$2(c^2-16d^2)$

Now we are getting somewhere. The 16 can be written as $4^2$ and we are looking for squared values

Write as:

$2(c^2-(4d)^2)$

So using the standard form of $a^2-b^2=(a-b)(a+b)$ we write:

$2(c^2-(4d)^2)" "=2(c-4d)(c+4d)$

How do you factor 2c^2-32d^22c^2-32d^2?