Question

Se f(x)=x² -5x+6, calcule:
a) f(-2)
b) f(0)
c) Faça f(x)=0 e calcule x

Answer 1

a) f(-2)= (-2)²-5(-2)+6
4+10+6= 20
b) f(0)= (0)²-5(0)+6
0-0+6= 6
c) f(x)=0
x²-5x+6=0
Delta= b²-4ac
(-5)²-4*1*6
25-24= 1
-b±√delta/2a
5±1/2
x'= 3 x''=2