Question

Разложите на множители: а) 16x^4-81; б)x^2-x-y^2-y.

Answer 1

А)4х^2-9 . Б)(х^2-х)+(у^2-у)=х (х-1)+у (у-1)=(х+у)*(х-1)*(у-1)

Answer 2

$16x^4-81=(4x^2-9)(4x^2+9)=(2x-3)(2x+3)(4x^2+9)\\\\\\x^2-x-y^2-y=(x^2-y^2)-(x+y)=\\\\=(x-y)(x+y)-(x+y)=(x+y)(x-y-1)$