Inverese of one to one function
posted by Jessica on .
I don't understand how to find the inverese of a one to one function.
Find the inverese of the one to one function.
9. f(x)=4x+7
Is the inverese suppose to be
f^1(x)=x7/4?
12. f(x)= square root of x8
I don't understand how to find the inverese on this one.
16. f(x)= 4/(5x1)
I don't understand how to find the inverese on this one.

9. The inverse function gives you x back if the dependent variable is f(x). Call f(x) "y"
y = 4x + 7
x = (1/4) (7y)
Now you can switch y and x, since it is a "dummy" variable anyway.
f^1 (x) = (7x)/4
12. y = (sqrt x)  8
y+8 = sqrt x
(y+8)^2 = x
f^1 (x) = (x+8)^2