If cosθ + sec θ = 8, find the value of cos2θ + sec2θ.

74 66 62 64

62

Formula I → [ cosθ = \(\frac{1}{secθ}\)] Formula II → [If x + \(\frac{1}{x}\) = n and x2 + \(\frac{1}{x^2}\) = n2 - 2 ] cosθ + \(\frac{1}{secθ}\) = 8 ⇒ cos2θ + \(\frac{1}{sec^2θ}\) = (8)2 - 2 ⇒ cos2θ + sec2θ = 64 - 2 = 62