4MA0 Higher January 2016 Paper 4 Q21
21

Diagram NOT accurately drawn
Calculate the length of \(BC\).
Give your answer correct to 3 significant figures.
(3)
| Scheme | Marks |
|---|---|
| (\(BC^2\) =) \(4.8^2 + 6.4^2 - 2 \times 4.8 \times 6.4 \times \cos 123^\circ\) | M1 |
| (\(BC^2\)=) 23.04+40.96+33.46..oe (=97.4(6262231)) | M1 |
| 9.87 | A1 |
| (3) |
Notes
M1: Correct use of cosine rule to find \(BC^2\)
M1: Correct order of operations & correct values
A1: awrt 9.87