How Do I Solve This Initial-Value Problem Correctly?

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Homework Help Overview

The discussion revolves around an initial-value problem involving differential equations and integration techniques. Participants are examining the relationship between the function f(x) and its derivative, as well as the integration of a specific rational function.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants are attempting to integrate the expression involving dy/dx and are discussing the correctness of their answers. There are questions about the differentiation of the function x^5 + 5x + 6 and its implications for the integration process.

Discussion Status

The conversation is ongoing, with some participants providing guidance on checking the original function and its derivative. There is recognition of different approaches to the integration problem, and some participants express confusion while seeking clarification on the methods used.

Contextual Notes

There are indications of uncertainty regarding the differentiation and integration steps, as well as references to similar problems in textbooks. Participants are navigating through the complexities of the problem without reaching a definitive conclusion.

morbello
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Have been looking at this problem .A few times nowI've come up with different answers.Its getting close to needing to know or wether, to just put in what i have.so I've placed a question on here to see if I am missing something.



The equations that are said to help are


[tex]\int\f'(x)/f(x) dx = In (f(x))+c (f(x)>0)[/tex]

dy[tex]/dx = x^4+1/x^5+5x+6 (x>-1)[/tex] is the equation to work off.


my work so far is

1[tex]/5 In (x^5+5)+c[/tex]
 
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your answer is nearly correct...you are just missing something...check back to what f(x) is and what your answer is...
 
so the x^5+5x+6 does not differeniate to become x^5+5 ok

there are a few activitys in my books that are like it.
 
morbello said:
so the x^5+5x+6 does not differeniate to become x^5+5 ok

there are a few activitys in my books that are like it.

[tex]\int \frac{x^4+1}{x^5+5x+6} dx[/tex]

Let [itex]t=x^5+5x+6 \Rightarrow \frac{dt}{dx}=5(x^4+1)[/itex]

[itex]\frac{dt}{5}=(x^4+1)dx[/itex]

[tex]\int \frac {x^4+1}{x^5+5x+6} dx \equiv \int \frac{1}{5} \frac{1}{t} dt[/tex]

and [itex]\int \frac{1}{x} dx = ln(x)+C[/itex]

[tex]\int \frac{1}{5} \frac{1}{t} dt = \frac{1}{5} lnt + C[/tex]
 
that blew me a little bit there.ive sat and looked at it a little and i think i know what you have done just i would not have thought off it. i think we did one function that was worked out that way.ill have to look it up tonight.
 

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