Question

№25, пожалуйста.
Заранее спасибо.

Answer 1

1
y²+y-12=0
y1+y2=-1 U y1*y2=-12⇒y1=-4 U y2=3
(y²+y-12)/(y²+8y+16)=(y+4)(y-3)/(y+4)²=(y-3)/(y+4
2
2m²-m-6=0
D=1+48=49
m1=(1-7)/4=-3/2 U m2=(1+7)/4=2
(4m²+12m+9)/(2m²-m-6)=(2m+3)²/(2m+3)(m-2)=(2m+3)/(m-2)
3
(a³|a²-a-1)/(a²+2a+1)=[a²(a+1)-(a+1)]/(a+1)²=(a+1)(a²-1)/(a+1)²=
=(a-1)(a+1)/(a+1)=a-1