Respostas

2013-08-13T02:25:24-03:00
x² -x -12=0 
a=1 b=-1 c=-12
∆=b²-4.a.c
∆=(-1)²-4.1.(-12)
∆=1+48
∆=49

x=-(-1)+ou-√49/2.1
x= 1+ou-7/2
x'=8/2=4
x''=-6/2=-3
s{-3;4}
3 5 3
2013-08-13T02:29:27-03:00