Question

Dada a função f(x)=2x²+5, determine o valor de:
A) f(5), f(-2) e f(0)
B) f para x=0,3
C) x para f(x) = 7

Answer 1

a) f(5)=2.5²+5=2.25+5=50+5=55
    f(-2)=2.(-2)²+5=2.4+5=8+5=13
    f(0)=2.0²+5=5
b) f(0,3)=2.(0,3)²+5=2.0,09+5=0,18+5=5,18
c) f(x)=7 -> 2x²+5=7 -> 2x²=2 -> x²=1 -> x=1