Prove math 10 points?

1. (cos2B+cos2A)/(cos2B-cos2A)=cot(A+B)cot(...

2. (cos2B-cos2A)/(sin2B+sin2A)=tan(A-B)

3. (sinA+2sin3A+sin5A)/(sin3A+2sin5A+sin7A)...
Update: Sorry there is technical prbm
here is:
1. = cot (A+B)cot(A-B)
3. =sin3A/sin5A

tq so much for helping!!!
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