OCR MEI C4 2012 June — Question 5 6 marks

Exam BoardOCR MEI
ModuleC4 (Core Mathematics 4)
Year2012
SessionJune
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicStandard trigonometric equations
TypeMixed sin and cos linear
DifficultyModerate -0.3 This is a straightforward trigonometric equation requiring the compound angle formula for sin(x+45°), basic algebraic manipulation, and solving a linear trigonometric equation. The 'show that' part guides students through the key step, making it slightly easier than average. The solution involves standard techniques with no novel insight required.
Spec1.05l Double angle formulae: and compound angle formulae1.05o Trigonometric equations: solve in given intervals

Given the equation \(\sin(x + 45°) = 2\cos x\), show that \(\sin x + \cos x = 2\sqrt{2}\cos x\). Hence solve, correct to 2 decimal places, the equation for \(0° < x < 360°\). [6]

Question 5:

5 (i)

5 (ii)
AnswerMarks
YearLife
expectancyBirth rate
(births / 1000)
Question 5:
--- 5 (i) ---
5 (i)
--- 5 (ii) ---
5 (ii)
Year | Life
expectancy | Birth rate
(births / 1000)
Given the equation $\sin(x + 45°) = 2\cos x$, show that $\sin x + \cos x = 2\sqrt{2}\cos x$.

Hence solve, correct to 2 decimal places, the equation for $0° < x < 360°$. [6]

\hfill \mbox{\textit{OCR MEI C4 2012 Q5 [6]}}