Difficult Trig Limit
I seem to be having a tough time with this one limit problem:
I've tried doing multiple simplifications but I have the problem of constantly getting a which can't be right, as wolfram-alpha and the answer book is telling me that the answer is , which won't come from the zero multiplication!
Determine the limit of:
Don't suppose I could snag a push in the right direction? thanks!
If you can know L'Hopital's rule
lim [tan(x)-sin(x)]/x^3 = lim sin(x)/x lim (sec(x)-1)/x^2
= 1 lim[sec(x)tan(x)/2x
= lim [sec^2(x)tan(x) +sec^3(x)]/2