Practicing Success
Practicing Success
CUET Preparation Today
If cosθ + sec θ = 12 , find the value of cos2θ + sec2θ. |
152 142 146 144 |
142 |
Formula I → [ cosθ = \(\frac{1}{secθ}\)] and vice versa. Formula II → [If x + \(\frac{1}{x}\) = n and x2 + \(\frac{1}{x^2}\) = n2 - 2 ] cosθ + \(\frac{1}{cosθ}\) = 12 ⇒ cos2θ + \(\frac{1}{cos^2θ}\) = (12)2 - 2 ⇒ cos2θ + sec2θ = 144 - 2 = 142 |
