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The first thing we should do is we should differentiate
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with respect to why So if we have four why
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we square this we end up with 16. Why
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squared? Which means we now have integral from wonder
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, too, to pi times. Why Times square
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off one plus 16 y squared Do you want now
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a little bit of U substitution If you was one
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for 16 where I squared What's under the square root
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? Then D'You is gonna be 32. Why di
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roi, which means the limits of integration. Now
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change. We now have power over 16 on the
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outside and we have 17 to 65 squirt of u
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d y. Okay, time to integrate. When
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we integrate, we know we're gonna be using the
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power rule, which means we increase the exponents by
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one, and then we divide by the new extra
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plug it in are two bounds have been given and
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we know this could be written is our solution because
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they've said exact area so we can leave our exact
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area as this