If f(x) = 1/4x+2 and g(x) = −3x^2+2.

determine the value of −3 g(1) 
determine the value of f^−1(1) 

2 answers

you need f^-1 (x)
let y = f(x) = (1/4)x + 2
interchange x and y:
x = (1/4)y + 2
4x = y + 8
y = f^-1 (x) = 4x - 8
f^-1 (1) = 4(1) - 8 = -4

-3g(1) = -3(-3(1^2) + 2
= -3(-3) + 2 = 11
something tells me that
f(x) = 1/(4x+2)
since f(-1/4) = 1, f-1(1) = -1/4