I have tan(3x)cot(7x) and i need to get it in the form (sin(ax)/ax)/(sin(bx)/bx) for some a and b. I have use the tan(x)=sin(x)/cos(x) and cot(x)=cos(x)/sin(x) to get (sin(3x)/cos(3x))(cos(7x)/sin(7x)) and that is about as far as i got.

Could anybody help me to solve this rearrangement. Then I need to find the limit as x goes to zero. But i have to show it in the form stated above.

Thanks.