Factor polynomial $$ 81x^{2}-1 $$
Answer
$$ 81x^{2}-1 = ( 9x-1 )( 9x+1 ) $$
Explanation
Rewrite $ 81x^{2}-1 $ as:
$$ 81x^{2}-1 = (9x)^2 - (1)^2 $$Now we can apply the difference of squares formula.
$$ I^2 - II^2 = (I - II)(I + II) $$After putting $ I = 9x $ and $ II = 1 $ , we have:
$$ 81x^{2}-1 = (9x)^2 - (1)^2 = ( 9x-1 ) ( 9x+1 ) $$This page was created using
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