Evaluate the following integrals:


sin(A - B) = sinAcosB - cosAsinB


We can write


sin(A + B) = sinAcosB + cosAsinB


We can write


The given equation becomes




Denominator is of the form (a - b)(a + b) = a2 - b2


….(1)


We know sin2x + cos2x = 1


sin2x =1 - cos2x


Substituting the above result in (1) we get



…(2)


Let us assume



2sinx.cosx.dx=dt


sin2x.dx=dt


Substituting dt and t in (2) we get



= ln|t| + c


But t =


ln| | + c.


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