1MA0 Higher November 2013 Paper 2 Q26
26 The diagram shows triangle \(LMN\).
Diagram NOT accurately drawn
Calculate the length of \(LN\).
Give your answer correct to 3 significant figures. (5)
| Working | Answer | Mark | Notes |
|---|---|---|---|
| \(180 - 136 - \text{``}34.4\text{''}\) \(= 9.504\) | 3.73 | 5 | M1 for \(\dfrac{\sin L}{12.8} = \dfrac{\sin 136}{15.7}\) M1 for \(L = \sin^{-1}\left(\dfrac{\sin 136}{15.7} \times 12.8\right)\) or \(\sin^{-1} 0.566\ldots\) A1 for 34.4 - 34.5 M1 for \(\dfrac{LN}{\sin(180 - 136 - \text{‘}34.4\text{’})} = \dfrac{15.7}{\sin 136}\) or \(\dfrac{LN}{\sin(180 - 136 - \text{‘}34.4\text{’})} = \dfrac{12.8}{\sin \text{‘}34.4\text{’}}\) or \((LN^2 =)\ 15.7^2 + 12.8^2 - 2 \times 15.7 \times 12.8 \times \cos(180 - 136 - \text{‘}34.4\text{’})\) A1 for 3.73 - 3.74 |