# Math Help - please solve these questions

1. ## please solve these questions

any body help me to solve that questions.

2. You can use disks or shells. One is easier than the other. I'd use disks.

Find the limits by equating the functions:

$y^{2}=y+12$

y=-3 and 4

${\pi}\int_{-3}^{4}((y+12)^{2}-y^{4})dy$

Shells method is trickier.

$2{\pi}\int_{0}^{9}x(2\sqrt{x})dx+2{\pi}\int_{9}^{1 6}x(\sqrt{x}-(x-12))dx$

I'll leave the actual integration to you.

3. ## thanks,

Thanks for correcting me Galcutus. i would try myself next. !!

4. Originally Posted by aziz101
Thanks for correcting me Galcutus. i would try myself next. !!
Are you the same person as m777?