Question

Dada a função f: R-R definida por f (x)= a.x + b, com a, b pertencendo a R, calcule a e b, sabendo que f (1)=4 e f (-1)= -2.​

Answer 1

Resposta:

a = 3

b = 1

Explicação passo-a-passo:

$\mathsf{f(x) = ax + b}\\\mathsf{f(1) = 4}\\\mathsf{f(1) = a.(1) + b}\\\mathsf{a + b = 4}\\\mathsf{f(-1) = -2}\\\mathsf{f(-1) = a.(-1) + b}\\\mathsf{b - a = -2}\\\mathsf{b = a - 2}\\\mathsf{a + a - 2 = 4}\\\mathsf{2a = 6} \\\mathsf{a = 3}\\\mathsf{b = 1}$