How do you multiply $(10w - 1)(10w + 1)$ ?

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Answer 1 · 2015-07-01T16:43:59

$=color(blue)( 100w^2 - 1$

$(10w - 1)(10w + 1)$

The expression is of the form:
$color(blue)( (a-b)(a+b) = a^2 - b^2$

Here $color(blue)(a=10w, b=1$

$= (10w - 1)(10w + 1)$
$= (10w)^2 - 1^2$

$=color(blue)( 100w^2 - 1$

How do you multiply (10w - 1)(10w + 1)(10w - 1)(10w + 1)?