A ladder 5m long is leaning against a wall. If the lower end of the ladder slides away from the wall at the rate of .5 m/s, at what rate is the inclination theta of the ladder with respect to the ground changing when the lower end is 4m from the wall?

Question

sleepyjess · Answer

@TheSmartOne @ganeshie8

sleepyjess · Answer

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sleepyjess · Answer

Does this have to do with trig functions?

ganeshie8 · Answer

You may start with that diagram and use cosine ratio : 

$\cos \theta = \dfrac{x}{5}$

where $x$ is the bottom side

ganeshie8 · Answer

familiar with implicit differentiation ?

sleepyjess · Answer

Yes

ganeshie8 · Answer

Good. Implicitly differentiate above equation with respect to the time : $t$

(Don't forget the chain rule)

ganeshie8 · Answer

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