WEBVTT
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this question asked us to find the exact area of
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the serfs obtained by routine the curve about the X
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axis. Have they stated we're looking at between 1/2
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of one, So those are bounds and because we're
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rotating it, we know we need to add to
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pie. Not we know. Our original is X
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cubed over six plus one over to X. This
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is the original expression we've been given. We know
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this is also gonna be multiplied by why Prime squared
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. So one plus 1/4 ext the fourth, minus
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one house plus one over four ox the fourth and
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again, As I stated, this is the formula
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listed in the textbook where you've got, like,
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two pi when they've got why prime squared to two
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pi r squared or whatever the formula is how you
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consider it to be. We know now we take
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the integral. We do this by increasing the exponent
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by one and then dividing by the new exponents.
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You can also simple for the fractions as you go
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along. If that makes it easier for you to
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understand and remember our bouncer from 1/2 to 1 and
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this was given in the problem. Now that we
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have this, we know you need to plug end
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. So we're plugging in upper minus lower and you're
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probably gonna need a calculator for this. We end
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up with approximately 1.3 pie or 3.227