How do you factor completely: $100x^2 – 1$ ?

Question

7309 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-07-29T07:25:09

$color(blue)((10x-1)(10x+1)$

$color(blue)(a^2-b^2 = (a-b)(a+b)$

The same property can be applied for the above expression:

$100x^2-1$ , here $color(blue)(a=10x, b=1$

The expression can now be factorised as:
$100x^2-1 = (10x)^2 - 1^2 = color(blue)((10x-1)(10x+1)$

How do you factor completely: 100x^2 – 1100x^2 – 1?