Calculus question- differentiation

AI Thread Summary
The discussion revolves around finding the derivative dy/dx for the function y = (5e^(2+ix))/(3e^(1-2ix)). The user initially applies the quotient rule but struggles with simplification. After some back-and-forth, they successfully simplify the expression to y = (5/3)e^(1 + 3ix). The final derivative is determined to be dy/dx = 5ie^(1 + 3ix). The conversation concludes with the user expressing satisfaction with the resolution of their question.
tracey163
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Could someone please help me with the method and steps to this question:

Find dy/dx for the following:

y = (5e^(2+ix))/(3e^(1-2ix))
 
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Simplify it so it is of the form constant*e^(something) and then carry out differentiation of exponentials as you would.
 
This is the way I tried to do it:

(Quotient rule)
dy/dx = ((5ie^(2 + ix))(3e^(1-2x)) - (-6ie^(1 - 2ix))(5e^(2 + ix))) / ((3e^(1 - 2ix))^2)

= (15ie^(3 - ix) + 30ie^(3 - ix)) / (9(e^(1 - 2ix))^2)

= (45ie^(3 - ix)) / (9(e^91 - 2ix)^2)

= (5ie^(3 - ix)) / ((e^(1 - 2ix))^2)

And I'm not sure where to go from there its either wrong or it needs simplifying some more...
 
Ah thanks, yeah your right, I've got it :) it all makes perfect sense now :)

y = 5/3.e^(2 + ix - (1 - 2ix))

=5/3.e^(1 + 3ix)

dy/dx = 5ie^(1 + 3ix)

:D thanks!
 
You're welcome :-)
 
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