4MA0 Foundation June 2014 Paper 1 Q21
21

Diagram NOT accurately drawn
Calculate the length of \(PQ\).
Give your answer correct to 3 significant figures.
(3)
| Scheme | Marks |
|---|---|
| \(\sin 38 = \dfrac{PQ}{12.2}\) or \(\cos(90 - 38) = \dfrac{PQ}{12.2}\) oe | M1 |
| (“PQ” =) 12.2 × sin 38 or 12.2cos(90 – 38) oe | M1 |
| 7.51 | A1 |
| (3) | |
| (3 marks) |
Notes
M1: 12.2cos38 (9.61...) and \(12.2^2 - \text{"}9.61\text{"}^2\) (= 56.4..)
or correct statement of sine rule eg \(\dfrac{PQ}{\sin 38} = \dfrac{12.2}{\sin 90}\)
M1: \(\sqrt{\text{"}56.4\text{"}}\)
or correct expression for \(x\) eg (PQ) = \(\dfrac{12.2\sin 38}{\sin 90}\)
A1: awrt 7.51