1. ## find the volume

The region enclosed by the cone z2 = x2 + y2 between the planes z = 5 and z = 7

2. Originally Posted by Naseef
The region enclosed by the cone z2 = x2 + y2 between the planes z = 5 and z = 7
Okay, what is your difficulty? That looks like a pretty easy question. I would be inclined to use cylindrical coordinates because then z^2= x^2+ y^2 becomes just z= r.

the book say the answer is 228.28 but i never came out with this answer

4. Here it is in spherical. You did not state if you had to use a particular method.

$\displaystyle \int_{0}^{2\pi}\int_{0}^{\frac{\pi}{4}}\int_{5sec{ \phi}}^{7sec{\phi}}{\rho}^{2}sin{\phi} \;\ d{\rho}d{\phi}d{\theta}$

5. Originally Posted by Naseef
the book say the answer is 228.28 but i never came out with this answer
I ask again- what is your difficulty? You say you did not come out with 228.28. Well, good for you- the answer is NOT 228.28! Did you come out with something? Please show what you did.

(I think the problem is far simpler in cylindrical coordinates than spherical coordinates.)

6. (I think the problem is far simpler in cylindrical coordinates than spherical coordinates.)

Yes, it is indeed. Just showing another way to do it.