1. ## urgent help: limit

lim [tan(sinx)- sin(tanx)]/x^7, x -->0

Thanks a lot

2. Originally Posted by meongao
lim [tan(sinx)- sin(tanx)]/x^7, x -->0

Thanks a lot
Firstly, I would substitute $y = x^7$ into that formula, where you would get

$\lim_{y\to 0} \frac{\tan(\sin(y^{1/7})) - \sin(\tan(y^{1/7}))}{y}$

Then, use L'Hopital's rule to get rid of the denominator. I hope that helps.