# Trigonometry

2cos(x)-3tan(x)=3sec(x)

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1. tan= sin/cos

Let C mean cosine, S mean sine(x)

multiply by C
2C^2-3S=3
2(1-S^2)-3S=3

2S^2+3S+1=0
(2S+1)(S+1)=0
so you have the solution.

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bobpursley

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