So the problem is
?
You should know that, by the "fundamental theorem of calculus",
It is a little bit more complicated by the fact that the limits of integration are 9x and 3x but you can do this:
And the fact that the upper limit is not just "x" can be handled by setting y= 3x in the first integral and y= 9x in the second:
The derivative of [b]with respect to y[/tex] is just and the derivative with respect to x is (by the chain rule) that times the derivative of y with respect to x.