# Area of a surface of revolution around the x-axis

Can the Surface area of a revolution be NEGATIVE? I am calculating this in parametric equations?

finally I hope this is the right forum to ask this question.

## Answers and Replies

sylas
Science Advisor
Can the Surface area of a revolution be NEGATIVE? I am calculating this in parametric equations?

finally I hope this is the right forum to ask this question.

Yes.

It is quite common for negative areas to show up in some context when you distinguish the inside and the outside of a surface. Depending on how you set up the formulae, you may have a case like this. Depending on what you are trying to find, you may need to alter the formula.

Cheers -- sylas