Answer:
f (
x
) −
1 =
(
1/
4 x
) −
2.
Step-by-step explanation:
For inverse function, the x and y interchanges and then make y the subject again of the equation. See the working out below:
f (
x
) = 4
x + 8
f (
x
) = y
y = 4
x + 8
x = 4
y +
8 ----- interchanging y and x
Now make y the subject of the equation:
x = 4
y + 8
−
4
y = -
x + 8
y = (
−
1/
4 )
. − x
+ (
−
1/
4 ) .8
y = (
1/
4 x
) −
2
So the inverse function is:
f (x) −
1 = (
1/
4 x
) −
2
