Question

Calcule o valor numérico das expressões
3x²-5x+6=
a)X=0
b)X=1
c)X= -1
d)X= 2
e)X= -2

Answer 1

a) 3·0²-5·0+6 = 3·0-5·0+6 = 0-0+6 = 6
b) 3·1²-5·1+6 = 3·1-5·1+6 = 3-5+6 = 4
c) 3·(-1²)-5·(-1)+6 = 3·(-1)-5·(-1)+6 = -3+5+6 = 8
d) 3·2²-5·2+6 = 3·4-5·2+6 = 12-10+6 = 8
e) 3·(-2²)-5·(-2)+6 = 3·(-4)-5·(-2)+6 = -12+10+6 = 4