The easiest way to do this problem is to put everything in terms of cosines and sines. So we're going to get X over sine 9X, cosine 4X. Now when I rewrite this, I'm always going to pull out my sine portions and I'm going to put everything that doesn't have a sine portion way down at the end. So in order for this to go to one, I need a 9X on top. If I put a 9X on top, I have to also put a 9X on bottom to keep the equation balanced. So now we have the limit as X approaches zero of nine X over sine of 9X times, the X on top and the X on bottom are going to cancel. So we get a placeholder of one on top and nine cosine 4X on bottom. Remember it's the limit of that whole thing. So this first part when I put an X goes to 0 is going to be one 1 / 9 cosine of 0 is one for a final answer of 1 ninth.