Find dy/dx given that y = 1 - cos x / sin x
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Answer:
tan x
Step-by-step explanation:
The given function y is a quotient, so we must apply the quotient rule first. Recall that (d/dx)cos x = -sin x and that (d/dx)sin x = cos x.
Then the derivative of the given quotient is:
(sin x)[0 - (-sin x)] [sin x]^2
dy/dx = --------------------------- = ----------------- = 1
[sin x]^2 [sin x]^2