Question

разложите на множители: x²y+1-x²-y²

Answer 1

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