Respostas

2013-09-26T20:14:58-03:00
F(x)=  2x+3
1 = 2x+3
1-3 =2x
-2/-2 = x
x= -1
f(x)=  2*-1+3 =1

B) f(x)=0
2x+3=0
2x=0-3
x=-3/2
x=-1,5
B) f(x)=2*(-1,5)+3=0

C) f(x)=3
2x+3=3 
se imaginarmos 2*0+3 =3
x=0

f(x)=0,75
2x+3=0,75
2x=0,75-3
x=-2,25/2
x=-1,125
f(x)=0,75
2*(-1,125)+3=0,75
2 5 2