Question

determine o polinomio p(x) = ax + b, tal que p(2) = 2 e p(5) = 11

a) p(x) = -3 + 4
b) p(x) = x - 4
c) p(x) = 4x - 3
d) p(x) = 3x
e) p(x) = 3x - 4

Answer 1

p(x) = ax + b

p(2) = 2a + b = 2
b = 2 - 2a ← importante.

p(5) = 5a + b = 11
5a + 2 - 2a = 11
3a = 11 - 2
3a = 9
a = 9/3
a = 3

→b = 2 - 2a
b = 2 - 2.3
b = 2 - 6
b = -4

p(x) = 3x - 4

Alternativa E.