Volume of a solid

[Lizzy]

I've tried this problem so many times already and I just can't get the right answer...I know the volume has to be taken in respect to y....

find the volume of the solid bounded by x=7y^2, y=1, x=0, about the y-axis...thanks for the help

 

[galactus]

You can use shells or disks.

DISKS:

$\displaystyle {\pi}\int_{0}^{1}(7y^{2})^{2}dy$

SHELLS:

$\displaystyle 2{\pi}\int_{0}^{7}x(1-\sqrt{\frac{x}{7}})dx$

 

[stapel]

I've tried this problem so many times already and I just can't get the right answer.

Unfortunately, since you have not shown any of your efforts, I'm afraid it is not possible for us to find where you might be going wrong (or to determine if the book contains a typo in the solutions). Sorry!

Eliz.