If `cos (x-y) = a cos (x + y)`, then `cot x cot y ` is equal to

If cos (x-y)=3 * cos (x+y) , " then " cot x* cot y=

What is ( tan x + tan y ) ( 1 - cot x cot y ) + ( cot x + cot y ) ( 1- tan x tan y ) equal to ?

If cot^(2)x =cot(x-y) cot(x-z) , then cot(2x) is equal to (where x ne +-pi/4 )

If tan A - tan B = x and cot B - cot A =y , then what is cot ( A -B) equal to ?.............. A) 1/x +ya B) (1)/(xy) C) (1)/(x) -(1)/(y) D) (1)/(x) +1/y

If a cos (x + y) = b cos (x - y), show that (a + b)tan x = (a - b) cot y.

If tan^(-1)x + tan^(-1)y = (2pi)/(3) , then cot^(-1) x + cot^(-1)y is equal to

If cot^(2)x=cot(x-y)*cot(x-z) , then cot2x is equal to (x!= pm pi/4)

If cot^(2)x=cot(x-y)*cot(x-z) , then cot2x is equal to (x!= pm pi/4)