If \(\rm \sin θ+\cos θ=\frac{\sqrt{11}}{3}\), then what is tan θ + cot θ equal to?
9
The correct answer is 9.
(\sin \theta + \cos \theta)^2 = \sin^2 \theta + \cos^2 \theta + 2 \sin \theta \cos \theta = 1 + 2 \sin \theta \cos \theta Similarly, when you square the difference: (\sin \theta - \cos \theta)^2 = \sin^2 \theta + \cos^2 \theta - 2 \sin \theta \cos \theta = 1 - 2 \sin \theta \cos \theta These expansions are very useful in solving trigonometric problems where sums or differences of sine and cosine are given, and products or other related functions like tangent and cotangent need to be found.
If $M = \sqrt{\frac{1+\cos A}{1-\cos A}} - \text{cosec} A - \cot A$, and A is an acute angle, then value of M is