MHB How to calculate LCM for rational equations ?

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To calculate the least common multiple (LCM) for rational equations, first factor all denominator polynomials completely. Next, create a list of each unique factor, ensuring to include the highest power of each factor present in any denominator. The resulting list of factors and their powers constitutes the LCM. For example, from the denominators 4x, x², and 2x², the LCM is determined to be 4x². Understanding the importance of expressing factors in their simplest form can help clarify the process.
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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 .
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

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