Răspunsuri

2014-05-04T04:02:44+03:00
(x+1)²+2(x-7)+1=
x²+2x+1+2x-7+1=
x²+4x-12=
(x-2)(x+6)
a)(x-2)(x+6)=0
x-2=0⇒  x=2
x+6=0⇒  x=-6
S={-6, 2}
b) E(-1)= (-1)²-4·(-1)-12=1-4-12=-15
sau E(-1)=(-1-2)(-1+6)=(-3)·5=-15