heres what i've had so far

heres the function

f(x) = x / x - 1...... i derived it which came out to f'(x) = -1 / (x - 1)^2..... I set the denominator equal to zero to solve for the critical number, the critical number is x = 1.... then i used a number line to determine where the function is increasing or decreasing to verify that 1 is a relative extrema.... but the problem is when i plug in the numbers to the left of 1 and the numbers to the right of 1, i get negative numbers which indicates that the function is decreasing, what should i do? is there not a relative max or min?? im very confused...