A robotic arm rotates such that its displacement angle α\alphaα in radians satisfies the drive torque equation:
3sinα(4cot22α−5)=8secα 3 \sin \alpha (4 \cot^2 2\alpha - 5) = 8 \sec \alpha 3sinα(4cot22α−5)=8secαShow that this equation can be expressed in the form
12csc22α−16csc2α−27=0 12 \csc^2 2\alpha - 16 \csc 2\alpha - 27 = 0 12csc22α−16csc2α−27=0Hence, for 0<α<π20 < \alpha < \frac{\pi}{2}0<α<2π, determine the possible values of the displacement angle α\alphaα, giving your answers to 3 significant figures.
42 exam-style questions on WJEC A Level Maths 1.5.5 Trigonometry. Each one has a worked solution and a mark scheme showing where the marks go.