Find the smaller of the two regions created by the curves x+7y=25 and x^2+y^2=25.
Last edited by Chris L T521; Dec 12th 2010 at 02:59 PM. Reason: Restored original post.
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Originally Posted by nickels Find the smaller of the two regions created by the curves x+7y+25 You'll need an equals sign for this if the question is to make sense, do you mean x+7y=25? Originally Posted by nickels and x^2+y^2=25. This is a circle centred at the origin, what is it's radius?
oh yes, sorry i meant x+7y=25
Last edited by Chris L T521; Dec 12th 2010 at 03:02 PM. Reason: Restored original post.
I would say the area is equal to $\displaystyle \displaystyle \int_a^b\sqrt{25-x^2}- \frac{25-x}{7}~dx $ where $\displaystyle a$ and $\displaystyle b$ are the intersections between the two functions. Do you follow?
Yes, I follow, but when I try to solve the integral, I mess up
Last edited by Chris L T521; Dec 12th 2010 at 03:03 PM. Reason: Restored original post.
Originally Posted by nickels Yes, I follow, but when I try to solve the integral, I mess up Separate into two parts $\displaystyle \displaystyle \int_a^b\sqrt{25-x^2}~dx-\int_a^b \frac{25-x}{7}~dx$ For the first part use the substitution $\displaystyle x=5\tan u$ the second one is a gimme!
I'm still a little lost
Last edited by Chris L T521; Dec 12th 2010 at 03:04 PM. Reason: Restored original post.
Why did you delete your posts?
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