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प्रश्न
A kite is being pulled down by a string that goes through a ring on the ground 8 meters away from the person pulling it. If the string is pulled in at 1 meter per second, how fast is the kite coming down when it is 15 meters high?
उत्तर
x2 + h2 = y2
`\implies` x2 + 225 = y2
Given, `dy/dx` = 1 m/sec
Differentiating w.r.t ‘t’
`2xdx/dt = 2ydy/dt`
`8 xx dx/dt = 17 xx 1`
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