Домашняя работа по алгебре

1
(64b^2+128b+64)/b=64(b^2+2b+1)/b=64(b+1)^2/b
4/b+4=(4+4b)/b=4(1+b)/b
64(b+1)^2/b : 4(1+b)/b=64(b+1)^2/b * b /4(b+1)=16(b+1)
16(b+1)=16(-15/16+1)=16*1/16=1
2
(x^2y-x^2)+(1-y)=x^2(y-1)-(y-1)=(y-1)(x^2-1)=(y-1)(x-1)(x+1)
3
a(a+4)/(a+4)^2=a/(a+4)
a=(a+4)=-2/(-2+4)=-1
4
2x^2-3x>0
x(2x-3)>0
x1=0
x2=1,5
-----(+)----(0)------(-)-----(1,5)-----(+)----
(-∞,0) U (1,5;+∞)