Re: Calculate area of x-y

Quote:

Originally Posted by

**tammyl** Could someone please check my work?

$\displaystyle \int \int_D (x-y) dA$

where D is bounded by $\displaystyle y=\sqrt{x}$ and $\displaystyle y=x^2$

I evaluated the double integral as

$\displaystyle \int_0^1 \int_{x^2}^{\sqrt{x}} (x-y) dy dx$

Solving the definite integral, the answer got was $\displaystyle \frac{1}{15}$.

Is this correct?

Check your math. The answer is 0.

-Dan

Re: Calculate area of x-y

Scary that I manage the calculus and mess up the adding of fractions.

Thank you greatly for your help!!!

Re: Calculate area of x-y

Quote:

Originally Posted by

**tammyl** Scary that I manage the calculus and mess up the adding of fractions.

Thank you greatly for your help!!!

It's a more common problem than you might think. (Beer)

-Dan

Re: Calculate area of x-y

Quote:

Originally Posted by

**tammyl** Scary that I manage the calculus and mess up the adding of fractions.

Yes, it means you are destined to be a mathematician!

Be afraid. Be very afraid!

Quote:

Thank you greatly for your help!!!