O-LevelAdditional MathematicsTrigonometry4037/12 · Oct/Nov 2012 · Q65 Marks
[Figure 6.1] Using sin15° = √2/4 (√3 - 1) and without using a calculator, find the value of sinθ in the form a + b√2, where a and b are integers.
- Using sin15° = √2/4 (√3 - 1) and without using a calculator, find the value of sinθ in the form a + b√2, where a and b are integers.[5]
This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.
Mark scheme
Marking points from the official mark scheme (Oct/Nov 2012). The mark or mark type is shown in brackets.
- [B1] If sin 15° is not used, then no marks are available
- [B1] B1 for correct statement of the sine rule
- [M1] M1 for correct manipulation to obtain sin θ = an expression in surd form
- [M1] M1 for attempt to obtain 2√2, 18√2 or reasonable attempt at simplification of their numerator
- [M1] M1 for attempt to rationalise, must see an attempt at simplification.
- [A1]
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →