Question

Разложите на множители
a^2+2ab+b^2-c^2+4cd-4b^2

Answer 1

$a^2+2ab+b^2-c^2+4cd-4b^2 = \\ = (a^2+2ab+b^2)-(c^2 - 4cd + 4b^2) = \\ = (a + b)^{2} -(c - d )^{2} = \\ = (a + b - c + d)(a + b + c - d)$