Is there a better way to integrate this

  • Thread starter Thread starter Dell
  • Start date Start date
  • Tags Tags
    Integrate
Click For Summary
SUMMARY

The best method to integrate the function f(x) = x²/(2x + 3) involves performing polynomial long division first, as the degree of the numerator exceeds that of the denominator. After dividing, the result will yield a polynomial P(x) and a proper fraction, allowing for simpler integration techniques. The integration can then be completed using variable substitution for the proper fraction, specifically integrating C/(2x + 3) as part of the process.

PREREQUISITES
  • Understanding of polynomial long division
  • Familiarity with integration techniques, specifically integration by substitution
  • Knowledge of improper rational functions
  • Basic calculus concepts, including integration of polynomials
NEXT STEPS
  • Study polynomial long division in detail
  • Learn about improper rational functions and their integration
  • Explore variable substitution methods in calculus
  • Practice integrating various rational functions to solidify understanding
USEFUL FOR

Students and professionals in mathematics, particularly those studying calculus, as well as educators looking for effective integration techniques for rational functions.

Dell
Messages
555
Reaction score
0
what is the best way to integrate this functio, i integrated in parts

f(x)=x2/2x+3


i split the top of the fraction and then integrated the x2 half using integration in parts, but its just long and lots of place to make mistakes.
 
Physics news on Phys.org
I would try to rid of the top bit. Here is a hint [tex]x^2=\frac{1}{4}((2x-3)(2x+3) + 9)[/tex].

Good luck
 
Dell said:
what is the best way to integrate this functio, i integrated in parts

f(x)=x2/2x+3


i split the top of the fraction and then integrated the x2 half using integration in parts, but its just long and lots of place to make mistakes.

I assume you mean:
[tex]\frac{x^2}{2x+3}[/tex]

Note the degree of the numerator is higher than that of the denominator. (Improper rational function like an improper fraction.)
You should first carryout long division of the polynomials (and check by re-multiplying).
You will then get a polynomial plus a proper fraction. Since the denom. has degree 1 the numerator (remainder) will be constant and you can integrate via simple variable substitution.

Carry out the long division:
[tex]2x+3)\overline{x^2 + 0x + 0}[/tex]

You should get:
[tex]P(x)+ \frac{C}{2x+3}[/tex]
where P is a polynomial

You can easily integrate:
[tex]\int P(x)dx + C/2 \int \frac{du}{u};\quad u = 2x+3[/tex]
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
2K
Replies
3
Views
2K
Replies
9
Views
3K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 15 ·
Replies
15
Views
2K
Replies
2
Views
1K
  • · Replies 4 ·
Replies
4
Views
4K
Replies
2
Views
1K