Question

Разложить на множители:
1-4x^2-4xy-y^2

Answer 1

$1-4x^2-4xy-y^2=1-(4x^2+4xy+y^2)=1^2-(2x+y)^2= \\ =(1-(2x+y))(1+(2x+y))=(1-2x-y)(1+2x+y)$