Derivative of e^t sin(2t) using the product rule

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quicksilver123
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Mod note: Changed title from "Differential Euler's Number"
1. Homework Statement

Find the derivative.
f(t)=etsin2t

The Attempt at a Solution



f'(t)=etsin2t(sin2t)(cos2t)(2)

However the book seems to say that there should be an extra "t" in the solution. Some help?
 
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quicksilver123 said:

Homework Statement


Find the derivative.
f(t)=etsin2t

The Attempt at a Solution



f'(t)=etsin2t(sin2t)(cos2t)(2)
This is incorrect. It should be ##f'(t) = e^{t\sin(2t)} \cdot \frac d{dt}(t \sin(2t))##
To get that last derivative you need to use the product rule and the chain rule, in that order.
quicksilver123 said:
However the book seems to say that there should be an extra "t" in the solution. Some help?
 
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