4MA0 Foundation June 2017 Paper 2R Q25
25
Diagram NOT accurately drawn
Work out the value of \(x\).
Give your answer correct to 3 significant figures.
(3)
| Scheme | Marks |
|---|---|
| (\(x^2\) =) \(18^2 - 13^2\) or \(324 - 169\) or 155 | M1 |
| (\(x\) =) \(\sqrt{18^2 - 13^2}\) or \(\sqrt{\text{"}155\text{"}}\) | M1dep |
| 12.4 | A1 |
| (3) | |
| (3 marks) |
Notes
M1: Squaring and subtracting
M1dep: For square rooting
A1: Accept 12.4 – 12.46 inclusive
Alternative Methods - Using Trigonometry
| Scheme | Marks |
|---|---|
Eg \(\sin^{-1}\left(\dfrac{13}{18}\right)\) and \(18\cos\text{"}46.2(382...)\text{"}\) oe or \(\cos^{-1}\left(\dfrac{13}{18}\right)\) and \(18\sin\text{"}43.7(617...)\text{"}\) oe | M2 |
| 12.4 | A1 |
Notes
M2: For a complete method
A1: Accept 12.4 – 12.46 inclusive