Answers

2014-02-14T22:24:07+08:00
1) tan 1/2θ + cot 1/2θ=2cscθ
1-cosθ/sinθ + 1+cosθ/sinθ
1-cosθ+1+cosθ/sinθ
removed -cosθ and +cosθ
so: 2/sin
2/1/csc
2cscθ

2) sin3θ = 3sinθ - 4sin³θ

3)tan³θ = 3 tanθ - tan³θ
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