If `N=(1-cos4beta)/(sec^2 2beta-1)+(1+cos4beta)/(cosec^2 2beta-1)` then `(log)_(0. 25)N` is equal to: `-2` (2) `-1` (3) `-1/2` (4) `1/2` (5) 0

If cos alpha=(2cos beta-1)/(2-cos beta) then tan (alpha/2) is equal to

cos 2 alpha =(3 cos 2 beta -1)/( 3-cos 2 beta), then tan alpha=

If |{:(1,cos alpha, cos beta),(cos alpha, 1 , cos gamma ),(cos beta, cos gamma , 1):}|=|{:(0,cos alpha, cos beta),(cos alpha , 0 , cos gamma),(cos beta, cos gamma, 0):}| then the value of cos^2 alpha + cos^2 beta + cos^2 gamma is : (a) 1 (b) 1/2 (c) 3/8 (d) 9/4

Show that cos^(-1) ((cos alpha+cos beta)/(1+cosalpha cosbeta))=2 tan^(-1)(tan (alpha/2) tan (beta/2))

Prove that (sin alpha cos beta + cos alpha sin beta) ^(2) + (cos alpha coa beta - sin alpha sin beta) ^(2) =1.

If cos(alpha-beta)=3sin(alpha+beta),t h e n 1/(1-3sin2alpha)+1/(1-3sin2beta)= (a) 1/2 (b) (-1)/2 (c) 1/4 (d) (-1)/4

alpha and beta are acute angles and cos2alpha = (3cos2beta-1)/(3-cos2beta) then tan alpha cot beta =

Let -pi/6 beta_1 and alpha_2 >beta_2 , then alpha_1 + beta_2 equals:

If 3cosalpha=2cos(alpha-2beta), then tan(alpha-beta) tanbeta= (A) 5 (B) -5 (C) 1/5 (D) -1/5

If cos(alpha-beta)=3sin(alpha+beta),t h e n1/(1-3sin2alpha)+1/(1-3sin2beta)= 1/2 (b) (-1)/2 (c) 1/4 (d) (-1)/4