Foundation November 2024 Paper 2 Q22
22 Use trigonometry to work out the value of \(x\). [3 marks]
Not drawn accurately
| Answer | Mark | Comments |
|---|---|---|
| Alternative method 1 – using sin 40 | ||
| sin chosen or used | M1 | |
| \(21 \times \sin 40\) | M1dep | accept \(21 \times [0.64, 0.643]\) |
| [13.49, 13.5] | A1 | |
| Alternative method 2 – using cos 50 | ||
| \(\cos (90 - 40)\) | M1 | |
| \(21 \times \cos (90 - 40)\) | M1dep | oe accept \(21 \times [0.64, 0.643]\) |
| [13.49, 13.5] | A1 | |
| Alternative method 3 – finds base then uses Pythagoras | ||
| \(21^2 - (21 \sin (90 - 40))^2\) | M1 | oe complete method except square root |
| \(\sqrt{21^2 - (21 \sin (90 - 40))^2}\) or \(\sqrt{[182.2, 182.22]}\) | M1dep | oe |
| [13.49, 13.5] | A1 | |
Additional guidance
| Check diagram for working | |
| Allow correct use of sine rule to indicate sin | |
| Ignore rounding or truncating after the correct answer is seen eg answer 14 after 13.5 seen | M1M1A1 |
| \(\sin 40 \times 21\) | M2 |
| sin may be indicated by eg circling S in SOH CAH TOA | |
| Do not accept answers from full sized or scale drawing | |
| sin 50 used (unless using Alt 3) | M0 |