| Exam Board | Edexcel |
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| Module | C2 (Core Mathematics 2) |
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| Year | 2009 |
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| Session | January |
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| Topic | Trig Equations |
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8. (a) Show that the equation
$$4 \sin ^ { 2 } x + 9 \cos x - 6 = 0$$
can be written as
$$4 \cos ^ { 2 } x - 9 \cos x + 2 = 0$$
(b) Hence solve, for \(0 \leqslant x < 720 ^ { \circ }\),
$$4 \sin ^ { 2 } x + 9 \cos x - 6 = 0$$
giving your answers to 1 decimal place.