f "2sin^(2)beta-cos^(2)beta=2",then "beta" is (a) "0^(@)" (b) "90^(@)" (c) "45^(@)" (d) "30^(@)"

7.If 2sin^2beta-cos^2beta=2 , then beta is A)0° B)90° C)45 ° D)30°

If sin(theta+alpha)=a,cos^(2)(theta+beta)=b, then sin(alpha-beta)=

If cos(alpha+beta)=0 then sin(alpha+2beta)=

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

Simplify 2sin^2beta+4cos(alpha+beta)sinalphasinbeta+cos2(alpha+beta)

If A=[(cos^(2)alpha, cos alpha sin alpha),(cos alpha sin alpha, sin^(2)alpha)] and B=[(cos^(2)betas,cos beta sin beta),(cos beta sin beta, sin^(2) beta)] are two matrices such that the product AB is null matrix, then alpha-beta is

If (tan(alpha+beta-gamma))/("tan"(alpha-beta+gamma))=(tangamma)/(tanbeta),(beta!=gamma) then sin2alpha+sin2beta+sin2gamma= (a) 0 (b) 1 (c) 2 (d) 1/2

If "cot"(alpha+beta)=0, then "sin"(alpha+2beta) can be (a) -sinalpha (b) sinbeta (c) cosalpha (d) cosbeta

If 2tanalpha=3t a nbeta,t h e ntan(alpha-beta)= (a) (sin2beta)/(5-cos2beta) (b) (cos2beta)/(5-cos2beta) (c) (sin2beta)/(5+cos2beta) (d) none of these

If cosalpha+cosbeta=0=sinalpha+sinbeta, then cos2alpha+cos2beta is equal to (a) -2"sin"(alpha+beta) (b) -2cos(alpha+beta) (c) 2"sin"(alpha+beta) (d) 2"cos"(alpha+beta)