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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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pier  {\object{\*\objclass \eqn}\rsltpict{\*\objdata 
.EQN 11 34 56 0 1
{0:a}NAME:8
}}  feet above the water and pulls in a rope attached to a buoy. If 
the rope is hauled in at the rate of  {\object{\*\objclass \eqn}
\rsltpict{\*\objdata 
.EQN 13 56 57 0 1
{0:b}NAME:2
}} ft/min,\par how fast is the buoy moving in the water when it is  {
\object{\*\objclass \eqn}\rsltpict{\*\objdata 
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
\fnil Georgia;}}\plain\cf1\fs24 \pard Let {\b\i x} be the distance of 
the buoy from the bottom of the pier,\par and {\b\i y} the length of 
the rope.}
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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g(c) of the buoy depending on its distance c from the pier?}
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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the speed of the buoy gets infinite\par if it approaches the pier. It 
smashes against the pier with infinite velocity.}
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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impossible, that means that the buoy will not meet\par the pier at the 
water line. Rather it will, shortly before hitting the wall, be lifted 
a little outside the water. }
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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stroboscopic way the approach of the buoy\par to the pier.\par When 
the length of the rope is  y, the slope of the rope would be}
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{\rtf\ansi \deff0{\colortbl;\red0\green0\blue0;}{\fonttbl{\f0\fcharset0
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