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#1 2009-08-15 19:29:13
- yamini
- Member
- Registered: 2009-08-10
- Posts: 2
trig
please help me solving this question
sinx+siny=3/4 sinx -siny=2/5 then tan(x-y/2)/tan(x+y/2)
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#2 2009-08-15 20:24:45
- Identity
- Member
- Registered: 2007-04-18
- Posts: 934
Re: trig
Seeing products of trig terms, the product to sum formula might be useful:
Now, to the other equations,
Adding,
Also, subtracting,
Now if x is in the first quadrant then we get
If x is in the second quadrant then we get
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