№1 y=2x^3-x^2-4x+5 y'=6x^2-2x-4 y'=0 6x^2-2x-4=0 D=4+96=100 x1=(2-10)/2=-4 x2=(2+10)/2=6 №3 y=x^2(2sinx+3) y'=2x(sinx+3)+2x^2cosx y'=2x(sinx+3+xcosx)