I am having a little trouble with two of the u-substitution problems on the review sheet.
Is this the correct way to solve problem 1(d)?
1 (d)
\int\frac{1}{xln(x)}dx
\int\frac{1}{xln(u)}dx
u=x
\frac{du}{dx}=1
du=dx
\int\frac{1}{xln(u)}du
ln(ln(x))+C
The next one I am unsure about is problem 2(b). Is this the correct way to do this one?
\int_{-1}^1 xe^{sin(x^2)}dx
\int_{-1}^1 xe^{sin(u)}dx
u=x^2
\frac{du}{dx}=2x
\frac{1}{2}du=xdx
\frac{1}{2}\int e^{sin(u)}du
u=(-1)^2 u=(1)^2
\int_{1}^1 \frac{1}{2}e^{sin(u)}
\frac{1}{2}e^{sin(1)}- \frac{1}{2}e^{sin(1)}=0