1.а^2-6а+6
2.4х^2+4ху+у^2
3.25b^2-20bx-20bxx-16x^2
4.4a^2-8a-(a^2-8a+16)=4a^2-8a-a^2+8a-16=3a^2-16
5.2b^2+4b+2-4b=2b^2+2
- х^3 + х(Х+2) = - х^3 +х( х^2 +4х +4)= - х^3 + х^3 +4х^2 +4х= 4х^2+4х =
= 4* (1/4)^2 + 4* 1/4 = 4 * 1/16 + 4*1/4= 1/4+1= 1 1/4 =1,25