When x x\,x is small and measured in radians, show that tan3xcos2x \tan 3x \cos 2x\,tan3xcos2x can be approximated by 3x−6x33x - 6x^33x−6x3.
Hence find an approximate value for tan0.3cos0.2\tan 0.3 \cos 0.2tan0.3cos0.2.
Calculate the percentage error in your approximation, giving your answer to two significant figures.
225 exam-style questions on WJEC A Level Maths 3.5 Trigonometry (A-level only), covering 3.5.1 Trigonometry (A-level only), 3.5.2 Trigonometry (A-level only), 3.5.3 Trigonometry (A-level only), 3.5.4 Trigonometry (A-level only), 3.5.5 Trigonometry (A-level only), 3.5.6 Trigonometry (A-level only), 3.5.7 Trigonometry (A-level only), and 3.5.8 Trigonometry (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.