7.If `2sin^2beta-cos^2beta=2`, then beta is
`A)0°`

`B)90°`

`C)45 °`

`D)30°`

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

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

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

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

If A=[[cos alpha, -sin alpha] , [sin alpha, cos alpha]], B=[[cos2beta, sin 2beta] , [sin 2 beta, -cos2beta]] where 0 lt beta lt pi/2 then prove that BAB=A^(-1) Also find the least positive value of alpha for which BA^4B= A^(-1)

Prove that : cos^2 theta + sin^2 theta cos 2 beta = cos^2 beta + sin^2 beta cos 2theta

If sin alpha+sin beta=a and cos alpha-cos beta=b then tan((alpha-beta)/2) is equal to-

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

Prove that 2 sin^2 beta + 4 cos(alpha + beta) sin alpha sin beta + cos 2(alpha + beta) = cos 2alpha

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