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All right.
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Today we're going to be evaluating this expression right here.
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We see it's a double definite integral.
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So the first thing we do with the double integral is evaluate the inside integral.
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If you notice the inside integral is with respect to y.
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So that means our y is the variable and x is a constant.
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So the first thing to do when you evaluate an integral is to pull out the constants.
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So let's pull out the constants.
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So let's pull.
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Pull our constant terms x and e to the x out of this middle integral.
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Rewrite the first one.
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Pull out the constant terms.
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Write that a little better.
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E to the x.
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Rewrite your inside integral.
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All that's left is y.
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Then, d, y, d, x.
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Okay? so we are evaluating this integral right here.
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I've already rewritten it.
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This screen so that we can evaluate it.
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So remembering your integration rules, we remember that the integral of y is one half y squared.
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Okay, now we need to evaluate it from one to two.
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One to two.
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To do that, you plug in two first, it's be a parentheses, plug in two, and then minus when you plug in one.
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Okay? 2 squared is 4 so we get 4 halves minus 1 squared is 1 so we get 1 half 4 halves minus 1 half is 3 halves so that's what this integral right here evaluates 2 okay so we can put 3 halves right here so we get integral from 0 to 1 x to the x, three halves, dx.
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I just replaced what's underlined here with three halves.
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Okay, so now we can evaluate this entire expression.
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Well, we have a definite integral again.
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So the first thing to do is pull out our constant terms.
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We notice now that we're integrating with respect to x.
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So x is a variable.
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So the only constant term we have is this three halves.
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So let's pull that out.
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So we have three halves.
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So we have three halves.
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0 to 1 x, e to the x, d x...