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john100
give the most general solutions to the equation 2sinxcosx-sin(2x)cos(2x)=0
Make 2sinxcosx to sin(2x) then factor out sin2x and solve. :)
Sin2X(1-Cos2X)=0 either Sin2X=0 which follows 2X=n*pie or x=n*pie/2 n=0 onwards integers or Cos2X=1 which follows 2X=2n*pie or x=n*pie n=0 onwards integers so our solution is union of the two above.