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alfers101
a man whose height is 1.8m is walking directly away from a lamp fast at contrite of 1.2m/s. if the lamp s 12m above the ground, find the rate of which shadow is lengthening
this is about time rates on differential calculus
have you tried drawing a picture yet
draw a picture, then figure out the equation where input is distance away from the lamp and out put is length of the shadow
|dw:1349318841236:dw|
then find the derivative in respect to t
dx/dt would be velocity which would be 1.2 and ds/dt would be rate the shadow increases over time