Solving x^4 - x^3 + x - 1 = 0 How is this done?

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To solve the equation x^4 - x^3 + x - 1 = 0, the discussion focuses on differentiating the function F(x) = e^(2x)/x^4 using the Quotient Rule. The differentiation leads to the expression 2x^4(e^(2x)) - 4x^3(e^(2x))/x^8. Participants clarify that while e^(2x) does not cancel, it can be factored out, aiding in simplification. The final answer is presented as 2e^(2x)(x-2)/x^5, emphasizing the importance of correctly managing the factors during simplification. Understanding these steps is crucial for successfully differentiating the function.
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How is this done?

x^4 - x^3
 
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You deleted the three sections, the first of which shows the complete problem and variables and data.
 
The original problem is to differentiate the following:

F(x) =

e^2x
x^4

So I applied the Quotient Rule and have it simplified to

2x^4(e^2x)-4x^3(e^2x)
x^8

I see that the e^2x's cancel and I don't understand how to simplify the rest.


The answer is
2e^2x(x-2)
x^5

I just can't put the pieces together, thanks!
 
Youre almost there. Just pull out some x's and the exponential, like, x^3 e^2x (2 x^1 - 4)/x^8.
Then cancel out those x^3 with those on the bottom, and pull out another two and you have the answer.
 
sdoman said:
The original problem is to differentiate the following:

F(x) =

e^2x
x^4

So I applied the Quotient Rule and have it simplified to

2x^4(e^2x)-4x^3(e^2x)
x^8
This (above) is correct.
sdoman said:
I see that the e^2x's cancel and I don't understand how to simplify the rest.
No, the e^(2x)'s don't cancel out. You can factor them out of each term, though.
sdoman said:
The answer is
2e^2x(x-2)
x^5

I just can't put the pieces together, thanks!
 
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