jika f(x)=1/x-5 untuk x tidak sama dengan 5, maka inversnya adalah...

f(x) = 1/(x - 5)
y = 1/(x - 5)
y(x - 5) = 1
xy - 5y = 1
xy = 5y + 1
x = (5y + 1)/y

f^-1(x) = (5x + 1) / x

f(x) = y = 1/(x - 5)
x - 5 = 1/y
x = 5 + (1/y)
x = f^-1 (y) = (5y + 1)/y

f^-1 (x) = (5x + 1)/x