Find , when

y = e3x sin 4x 2x

Let y = e3x sin 4x 2x


Take log both sides:


log y = log (e3x sin 4x 2x)


log y = log (e3x ) + log (sin 4x) + log (2x)



log y = 3x log e+ log (sin 4x) + x log 2 {log xa = alog x}


log y = 3x + log (sin 4x) + x log 2 {log e = 1}


Differentiating with respect to x:












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