SOLUTION: Verify the identity. cot (x- (pi/2)) = -tan x

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Question 979946: Verify the identity.
cot (x- (pi/2)) = -tan x
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!

(cos x/sin x)=cot x
Then use trig identities for (alpha - beta)
Looking at numerator:
cos x cos pi/2+sin x sin pi/2 is numerator=sin x; cos pi/2=0
Looking at denominator:
sin x cos pi/2 - cos x sin pi/2; sin pi/2=1; 0 -cos x=-cos x
First term of both is 0.
sin x/-cos x= -tan x