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1 vote
1 answer
393 views

Skepticism concerning Heaviside's "Cover-up Method" for partial fraction decomposition

I was reading this paper from MIT and it introduces Heaviside’s Cover-up Method for partial fraction decomposition. In that paper in Example $1$ it solves a problem using that method and just when ...
user avatar
1 vote
1 answer
64 views

Evaluation of a telescoping sum

I have come to a problem in a book on elementary mathematics that I don't understand the solution to. The problem has two parts : a.) Factorize the expression $x^{4} + x^{2} + 1$ b.) Compute the ...
scipio's user avatar
  • 595
0 votes
2 answers
61 views

Integration of rational of polynomials

I want to evaluate the indefinite integral for: $$ \int\frac{x^3+3x−2}{x^2-3x+2}dx,\quad \text{for } x>2 $$ I did long division and factoring, simplifying it to $$ \int x+3\,dx + \int\frac{10x-8}{(...
Hash88's user avatar
  • 115
0 votes
1 answer
82 views

About a statement of partial fraction in an answer

I'm reading this answer of The logic behind partial fraction decomposition, I think my question is too basic and not directly related to the answer so I don't comment there. I don't understand why: ...
Kindred's user avatar
  • 229
0 votes
1 answer
64 views

Polynom and decomposition

I need to know I can decompose into simple elements $$\frac X{(X+1)^4 (X^2 +1)}$$ What is the easiest way?
Lamloumi Afif's user avatar
2 votes
2 answers
501 views

What is this change of variable in a polynomial?

The autocovariance generating function, $\gamma(z)$, is defined as the $z$-transform of the autocovariance function, $\gamma_\tau$: $$ \gamma(z) = \gamma_0 + \gamma_1(z+z^{-1}) + \gamma_2(z^2+z^{-2}) +...
javlacalle's user avatar
2 votes
1 answer
180 views

1967 HSC 4 unit Mathematics Question 2

Screenshot from the examination paper [...asking about partial fraction decomposition of $$\frac{1 - abx^2}{(1-ax)(1-bx)} $$ and related formulas...] This question is taken from the New South Wales ...
Sean Reeves's user avatar
0 votes
1 answer
64 views

Algebraically solve for reciprocal of result of polynomial long division

How can I show the following relationship algebraically? $$\frac 1 {4-\frac2 x}=\frac1 4+\frac1 {8x-4}\ \ \ \ \forall x\ne\frac1 2$$ I tried to multiply by the conjuage $$\left(\frac 1 {4-\frac2 x}\...
Will Sherwood's user avatar
1 vote
1 answer
249 views

When are we allowed to match coefficients?

Related to this answer: Find k in $(1−2k)x^2−(3k+4)x+2=0$ given facts about the roots. In the partial fraction decomposition of $\frac{1}{(x-1)(x+1)} = \frac{A}{x-1} + \frac{B}{x+1}$, we have: $0x + ...
BCLC's user avatar
  • 13.7k
25 votes
5 answers
5k views

How does partial fraction decomposition avoid division by zero?

This may be an incredibly stupid question, but why does partial fraction decomposition avoid division by zero? Let me give an example: $$\frac{3x+2}{x(x+1)}=\frac{A}{x}+\frac{B}{x+1}$$ Multiplying ...
Argon's user avatar
  • 25.4k
7 votes
2 answers
565 views

Partial fraction of $\prod_{j=1}^{N}\frac{1}{(x-a_{j})^{n_{j}}}$

Does anybody know the partial fraction decomposition of $$ \prod_{j=1}^{N}\ \frac{1}{(x-a_{j})^{n_{j}}} $$ with all $a_{j}$ different and $n_j$ positive integers? I know you can get it with the ...
lcv's user avatar
  • 2,624
9 votes
3 answers
2k views

Partial fraction of $\frac{x^n}{(1-x)(1-2x)(1-3x)\ldots(1-nx)}$

How should you break $\displaystyle \frac{x^n}{(1-x)(1-2x)(1-3x)\ldots(1-nx)}$ into partial fractions?
Vafa Khalighi's user avatar