Question 2 - A-Level Maths

Exam Board	AQA
Module	FP3 (Further Pure Mathematics 3)
Year	2014
Session	June
Marks	8
Topic	First order differential equations (integrating factor)

Find the values of the constants $a$, $b$ and $c$ for which $a + b \sin 2 x + c \cos 2 x$ is a particular integral of the differential equation $$\frac { \mathrm { d } y } { \mathrm {~d} x } + 4 y = 20 - 20 \cos 2 x$$ [4 marks]
Hence find the solution of this differential equation, given that $y = 4$ when $x = 0$.
[0pt] [4 marks]
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