Quote:
Originally Posted by Dr Sardonicus
...
Inverse function
x = y^{3} + 2*y + 4, point (7, 1)
...

IMHO opinion your definition of the inverse function is not correct.
If y=f(x) the inverse function y=f
^{ 1}(x) will be such that f(g(x))=y this is obviously not the case your calculations. (For instance it is obvious that x=y
^{3} is not the inverse function of y=x
^{3}, since substituting x for your inverse function will give y=(y
^{3})
^{3}=x
^{9}.)
Jacob
See
Wikipedia : Inverse function for instance.