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# core 3 trigonometry watch

1. Hi, I've come across a question during my revision and I don't understand how the mark scheme has jumped from one piece of working out to another. They have gone from 3cos2x+3=sin2x to (sin2x)/(cos2x+1)
please can someone explain how they did this, I think its with a trig identity (maybe cos2x=2cos^2x-1) but I'm not sure. thanks
2. They factored the 3 out so: 3(cos(2x) +1) = sin(2x)
3 = (sin(2x))/(cos(2x)+1)
3. thanks so much

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