1. The problem statement, all variables and given/known data 1) I am having trouble with the questions, "Use the logarithmic derivative to find y' when y=((e^-x)cos^2x)/((x^2)+x+1) 2. Relevant equations (dy/dx)(e^x) = e^x (dy/dx)ln(e^-x) = -x ? 3. The attempt at a solution First I believe I put ln on each set of terms (Though I don't know why, so if someone could explain that to me that would be great). So I have lny=ln((e^-x)cosx^2) - ln((x^2)+x+1). And I know for the quotient rule for derivatives I subtract the denominator in the numerator and then square the denominator, so why do I not square the denominator in this case? Now I don't know if I'm suppose to take the natural logs of those or just take their derivatives or one and then the other. Taking the derivative I believe I get something like (1/y)(dy/dx)=(-x * 2cosx * -sinx^2 * 1/cosx^2) - (1/x^2 + 1/x) ... (I used the chain rule for ln(cosx^2) three times). And I suppose I could simplify that a bit, but I'm betting it's wrong so far. As you probably can tell I'm very very confused so thanks for any help.