Answer:
cot . (x- π/2)= - tanx
Explanation:
cot . (x- π/2)= - tanx
cot .x - cot π/2= - tanx
cot π/2= 1/tanπ/2
But tan π/2= ∞
cot π/2 = 1/∞= 0
cotx - 0= - tanx
cot x = - tanx
cosx/sinx= - sinx/cosx Putting values of cot and tan
cosx/ sinx ( sinx/cos x) = -sinx/cos x (sinx/cos x )
Multiplying both sides with sinx/cos x
1= - sin²x/cos²x
cos²x= - sin²x as cosx = -sinx