What is the derivative of z=(te^6t + e^7t)^5?

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Homework Statement


Find the derivative of the given function
z=(te^6t + e^7t)^5


Homework Equations





The Attempt at a Solution


5(te^6t + e^7t)^4
 
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That's wrong! Chain rule! Then product rule!
 
write
z=(te^6t + e^7t)^5=(t+e^t)^5*e^30t
 
Last edited:
lurflurf said:
write
z=(te^6t + e^7t)^5=(t+e^t)e^30t

You mean z=(t+e^t)^5*e^30t. And I don't see how that makes it easier. The original form for z is easy enough to differentiate if you use the rules.
 
They are both easy, but I thought the use of slightly fewer rules was an improvement.
(te^6t + e^7t)^5
power rule with chain rule
sum rule
product rule
derivative of an exponential with chain rule x2
derivative of the variable
total=9 rules (3 chain)
vs
(t+e^t)^5*e^30t
product rule
derivative of an exponential with chain rule
power rule with chain rule
sum rule
derivative of the variable
derivative of an exponential
total=8 rules (2 chain)
Though most important
(t+e^t)^5*e^30t is more aesthetically pleasing to my eye.
 
Well, now it's up to neutron star to pull off either one.
 
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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