Bryant Lam Hong Sheng's answer to Gigi's Secondary 4 A Maths question.

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Bryant Lam Hong Sheng
Bryant Lam Hong Sheng's answer
97 answers (Tutor Details)
1st
Part (a) should be relatively simple. Express the lengths of breadths of the rectangle in terms of sin and cos.

Part (b) requires the use of R formula in which R is always positive and alpha is always acute. By using the compound formula for cos (A - B) which is found in the mathematics formula sheet provided, i can derive the 2 equations and solve for R and alpha.

Part (c) should also be relatively simple. Just use double angle formula for sin and you will get your answer.