How to calculate LCM for rational equations ?

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Discussion Overview

The discussion revolves around the calculation of the least common multiple (LCM) for rational functions, focusing on the steps involved in factoring denominator polynomials and determining the LCM based on those factors. Participants explore the methodology and express confusion regarding the process.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants outline a step-by-step method for calculating the LCM of rational functions, emphasizing the importance of factoring denominator polynomials completely.
  • There is a discussion on the representation of factors, with some suggesting that writing out powers as products is unnecessary and that keeping them in power form is preferable.
  • Participants express confusion about the steps involved, questioning whether mistakes exist in the calculations presented.
  • One participant confirms that there are no mistakes in the previous posts, indicating agreement on the method while acknowledging the potential for confusion.

Areas of Agreement / Disagreement

Participants generally agree on the steps to calculate the LCM, but there is some confusion regarding the representation of factors and the clarity of the explanations provided. The discussion remains somewhat unresolved as participants seek clarification.

Contextual Notes

Some assumptions about the understanding of factoring and the notation used may be missing, leading to confusion among participants. The discussion does not resolve all uncertainties regarding the steps for calculating the LCM.

kupid
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To calculate an LCM for a rational function, follow these steps:
1. Factor all denominator polynomials completely.
2. Make a list that contains one copy of each factor, all multiplied together.
3. The power of each factor in that list should be the highest power that factor is
raised to in any denominator.
4. The list of factors and powers you generated is the LCM.

View attachment 6872

4x = 2.2.x , x2 = x.x , 2x2 =2.x.x

So LCM = 2.2.x.x = 4x2

I still don't understand this clearly ...
 

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Hey kupid,

Let's run through the steps.

kupid said:
To calculate an LCM for a rational function, follow these steps:
1. Factor all denominator polynomials completely.

$4x=2^2\cdot x,\quad x^2,\quad 2x^2 = 2\cdot x^2$

kupid said:
2. Make a list that contains one copy of each factor, all multiplied together.

$2\cdot x$

kupid said:
3. The power of each factor in that list should be the highest power that factor is
raised to in any denominator.

$2^2\cdot x^2$

kupid said:
4. The list of factors and powers you generated is the LCM.

$LCM=2^2\cdot x^2 = 4x^2$
 
Is there any mistake in the above post , because i am a bit confused .

To calculate an LCM
for a rational function, follow these steps:
1. Factor all denominator polynomials completely.
4x = 2.2.x = 22.x , x2 = x.x , 2x2 =2.x.x
2. Make a list that contains one copy of each factor from the "pairs of factors ", all multiplied together.

2.x

3. The power of each factor in that list should be the highest power that factor is
raised to in any denominator.

22.x2

4. The list of factors and powers you generated is the LCM

LCM = 22.x2 = 4x2
 
kupid said:
Is there any mistake in the above post , because i am a bit confused .

No mistake. That's fine. (Nod)

It's just that when we factor completely, there's little point in writing out a power as a product.
We can keep it as a power.
So instead of writing $7x^8=7\cdot x\cdot x\cdot x\cdot x\cdot x\cdot x\cdot x\cdot x$, we can just leave it as $7x^8$.
 
OK , Thanks a lot .
 

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