Question

упростите выражение:а)(z-7)(z+1)-(z+3)^2 б)2(3k-l)^2+12kl в)y^3+(5-y)(25+5y+y^2)

Answer 1

a) (z-7)(z+1)-(z+3)^2= z^2+z-7*z-7-(z^2+2*3*z+3^2)=z^2+z-7*z-7-z^2-6*z-9=
=-12*z-16