Derivative of exponential function

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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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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