In robotic kinematics, the equilibrium tilt angle α\alphaα of a stabilizer, measured in radians, is modeled by a balance of forces. This equilibrium occurs when the following equation is satisfied:
12sinαcosα2sinα+5=2tanα,sinα≠−2.5 \frac{12\sin\alpha \cos\alpha}{2\sin\alpha + 5} = 2\tan\alpha, \quad \sin\alpha \neq -2.5 2sinα+512sinαcosα=2tanα,sinα=−2.5Demonstrate that this equilibrium equation can be expressed in the form
6sin3α+2sin2α−sinα=0 6\sin^3\alpha + 2\sin^2\alpha - \sin\alpha = 0 6sin3α+2sin2α−sinα=0Determine the specific tilt angles α\alphaα in the interval −π2<α<π2-\frac{\pi}{2} < \alpha < \frac{\pi}{2}−2π<α<2π that satisfy this condition, giving your answers to 3 decimal places.
317 exam-style questions on OCR (MEI) A Level Maths 1.7 Trigonometry, covering 1.7.1 Solve right-angled triangles, 1.7.2 Definitions of sin, cos and tan for any angle, 1.7.3 Graphs of sin, cos and tan, 1.7.4 Exact values of trig functions (degrees), 1.7.5 Area of a triangle, 1.7.6 Sine and cosine rules, 1.7.7 Identity tan = sin/cos, 1.7.8 Identity sin^2 + cos^2 = 1, 1.7.9 Solve simple trigonometric equations, 1.7.10 Exact values of trig functions (radians) (A-level only), 1.7.11 Inverse trigonometric functions (A-level only), 1.7.12 Radians and degree conversion (A-level only), 1.7.13 Arc length and area of a sector (A-level only), 1.7.14 Small angle approximations (A-level only), 1.7.15 Sec, cosec and cot functions (A-level only), 1.7.16 Graphs of reciprocal trig functions (A-level only), 1.7.17 Pythagorean identities for sec and cosec (A-level only), 1.7.18 Compound angle formulae (A-level only), 1.7.19 Double angle identities (A-level only), 1.7.20 Expressions for a cos θ ± b sin θ (A-level only), 1.7.21 Use identities to solve equations (A-level only), 1.7.22 Proofs involving trigonometric functions (A-level only), 1.7.23 Trig to solve problems in context (A-level only), and 1.7 Trigonometry. Each one has a worked solution and a mark scheme showing where the marks go.