(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

P1

sin 2x + sqrt(2) sin (x - (pi/4)) = 1

P2

Two sides of a triangle are 5cm and 9cm long. The ratio of the opposite angles is 1:3. Determine the angles and the length of the third side of the triangle!

2. Relevant equations

sin(2&) = 2 sin&cos&

sin(& - §) = sin& cos§ - cos& sin §

3. The attempt at a solution

P1

With this problem I'm stuck at:

sin 2x + sqrt(2) sin (x - (pi/4)) = 1

sin 2x + sqrt(2) (sinx (1/2)sqrt(2) - cosx (1/2)sqrt(2)) = 1

sin 2x + sin x - cos x = 1

2 sinx cosx + sin x - cos x = 1

Here I have the equation in one angle, but not in one function. I guess I need to do some changing etc. But I really can't figure out where to start.

P2

Two sides are given and a ratio of opposite angles. I do not even know where to start on this one...help is greatly appreciated!

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# Homework Help: Q6 - Some Trigonometry questions

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