Date | November 2016 | Marks available | 3 | Reference code | 16N.1.sl.TZ0.2 |
Level | SL only | Paper | 1 | Time zone | TZ0 |
Command term | Find | Question number | 2 | Adapted from | N/A |
Question
Let sinθ=√53sinθ=√53, where θθ is acute.
Find cosθcosθ.
[3]
a.
Find cos2θcos2θ.
[2]
b.
Markscheme
evidence of valid approach (M1)
egright triangle, cos2θ=1−sin2θcos2θ=1−sin2θ
correct working (A1)
egmissing side is 2, √1−(√53)2√1−(√53)2
cosθ=23cosθ=23 A1 N2
[3 marks]
a.
correct substitution into formula for cos2θcos2θ (A1)
eg2×(23)2−1, 1−2(√53)2, (23)2−(√53)22×(23)2−1, 1−2(√53)2, (23)2−(√53)2
cos2θ=−19cos2θ=−19 A1 N2
[2 marks]
b.
Examiners report
[N/A]
a.
[N/A]
b.