Q11 of 805 Page 427

If 7 sin2θ + 3 cos2θ = 4, show that tan θ =

Given: 7 sin2 θ + 3 cos2 θ = 4


Since sin2 θ + cos2 θ = 1 …Equation 1


So the equation becomes


4 sin2 θ = 1


⇒ sin2 θ =


From Equation 1 we get


cos2 θ =


Since



⇒


Hence Proved


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