dy = d(e^(cos2x))(sin(x^2))= sin(x^2) d(e^(cos2x)) + e^(cos2x) d(sin(x^2)= sin(x^2) e^(cos2x) (-2sin2x)dx + e^(cos2x) cos(x^2) 2xdxy` = e^(cos2x)(sin(x^2)(-2sin2x) + 2xcos(x^2))