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:
