Question

If 90° < θ < 180° and cscθ = 3, then cotθ = _____.

Answer 1

$\text{Given that,}\\\\\csc \theta = 3\\\\\implies \csc^2 \theta = 9\\\\\implies 1+ \cot^2 \theta = 9\\\\\implies \cot^2 \theta = 8\\\\\implies \cot \theta = \pm \sqrt 8 = \pm 2\sqrt 2\\\\\text{Since,}~90^{\circ}< \theta < 180^{\circ},\\\\\cot \theta = -2\sqrt 2$