Problem 3

 3. Find the area between y = x-1 and x = 3 – y2.

NEED SKETCH

For this one, we need to use x dy instead of y dx. Sketch the dA element each way, and you’ll see that it won’t work using dx..

Now, find the end points: (The limits are now along the y axis.)

y + 1 = 3 – y2

y2 + y – 2 = 0

(y + 2)(y – 1) = 0         y = -2, 1

So:



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