Consumer Surplus, intergrals ...

These seem to be straightforward. Where are you having trouble?.

For the first two, you can use substitution.

1a: Let \(\displaystyle \L\\u=x^{2}, \;\ du=2xdx\)

1b. Let \(\displaystyle \L\\u=x^{2}=1, \;\ du=2xdx, \;\ \frac{du}{2}=xdx\)

2. where does the parabola cross the x-axis?. Those are your limits of integration.

3. Very basic DE, just use separation of variables.
 
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