Evaluate the definite integral:

Let


Also, let sinx – cosx = t


Differentiating both sides, we get,


(cosx + sinx) dx = dt


When x = 0, t = -1


And when , t = 0


Now,


(sinx – cosx)2 = t2


1 – 2 sinx.cosx = t2


Sin2x = 1 – t2


Putting all the values, we get the integral,








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