Упростить выражения: 3(x+1)^2-6x
(5x+1)(3x+4)-23(x-2)

3(х+1)²-6х=3(х²+2х+1)-6х=3х²+6х+3-6х=3х²+3=3(х²+1)(5х+1)(3х+4)-23(х-2)=15х²+3х+20х+4-23х+46=15х²+50=5(3х²+10)