Question
Question: General solution of the equation \(2\cos^{2}\theta - (\sqrt{2} + 1)\cos\theta - 1 + \frac{(\sqrt{2} ...
General solution of the equation 2cos2θ−(2+1)cosθ−1+2(2+1)=0is.
A
⇒
B
cosθ=4(2+1)±(2+1)2−28
C
⇒
D
None of these
Answer
cosθ=4(2+1)±(2+1)2−28
Explanation
Solution
On simplification, it reduces to
⇒
θ=2nπ±3π 2secθ+tanθ=1⇒cosθ2+cosθsinθ=1.