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This is problem number sixty six of the stuart calculus eighth edition, section two point three.
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The figure shows a fixed circle c one with equation quantity x minus one squared plus y squared equals one and a shrinking circle c two with radius r and center at the origin.
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P is the point zero.
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Come on.
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Our q is the upper point of intersection of the two circles, and our is the point of intersection of the line p q and the x axis.
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What happens to our c two shrinks? that is, as our burt zero from the right.
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So here we have another o.
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R.
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This is di figure that these problems referencing where we have the fix circle c one.
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We have the shrinking circle, too, which is currently centred about the origin.
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And it'll remain senator about origin but has a radius of are at this point, and we see that there's language through p and q.
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And where do they intersect? sex excess, that is the point are so to first approach this problem, we should understand what we're q lies at any point while this circle is shrinking, so we need to find what where point q is by equating the equation of the circle sea, too, with the equation of the circle sea one.
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The equation would foresee.
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One circle si won has given.
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However.
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The equation for setu is not given, but we can write that because it is centered at the origin.
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C two has an equation equal to x squared plus y squared equals r squared.
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So now that we have the equation for both circles, we will seek to sell for the intersection.
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Cue by equating these two equations, we will first do that by taking this equation and subjecting this equation.
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And so, for the ex co ordinate, it's a little out of x minus one quantity squared minus x squared.
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Why square minus what i scored.
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A zero equals one minus r squared.
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Here we expand.
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This term becomes x squared menace to x plus one minus x word equals to one minus r squared and we see here that x squared x squared the negatives were cancelled plus one on one side and plus one of the others have also cancelled.
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And if we solve for x, we should get one half r squared.
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We take this x value, plug it into the equation of c two in order for us to easily calculate thie.
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Why coordinate of q one f r squared his ex square.
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This plus y squared equals r squared.
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This is one fourth art of the fourth plus y squared equals r squared.
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That means that why squared equals r squared minus one fourth.
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Aren't you the fourth? if we rearrange the right side of this equation, we're able to affect her and an r squared and we're left with one minus one fourth r squared and then we take the square root.
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I'm good science and we get our times the square root of the quantity one minus one fourth r squared.
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So at this point, we should just confirm that q.
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The point for q is one half r squared for x, and then the white coordinate is our time to square root of one minus one fourth r squared.
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Okay, so we will use what we know about q and we won't know what we know about pee pee is at zero r q as thes coordinates...