Question

If fx)-5x-25 and - X+5, which expression could be used to verity gx) is the inverse of fx)? os. O6x-25).5 x5

Answer 1

To verify g(x) is the inverse of f(x), the value of f[g(x)] = x

f(x) = 5x - 25 and g(x) = 1/5 x + 5

so,

substitute with g(x) instead of x at f(x)

So,

f[g(x)] = 5 ( 1/5 x + 5 ) - 25

Or we can do the inverse, i mean find g[f(x)]

So,

g[f(x)] = 1/5 ( 5x - 25) + 5

so, the right expression to verify g(x) is the inverse of f(x) are;

5 ( 1/5 x + 5 ) - 25 OR 1/5 ( 5x - 25) + 5

so, check the options which one of them:

so, the answer is: the second option 1/5 ( 5x - 25) + 5