vickycorbett420
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(4/x - 1/2x)/(2/3x+3/4x)
help appreciated
help appreciated
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stuck on problem
- Thread starter vickycorbett420
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You didn't mention what the question was - it must be that you are to simplify the expression?(4/x - 1/2x)/(2/3x+3/4x)
help appreciated
The LCD of all four fractions is 12x. What happens if you multiply the expression by (12x)/(12x) = 1? that is, multiply both terms in the numerator and both terms in the denominator by (12x).
HallsofIvy
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\(\displaystyle \left(\frac{4}{x}- \frac{1}{2x}\right)\left(\frac{2}{3x}+ \frac{3}{4x}\right)= \left(\frac{4}{x}\right)\left(\frac{2}{3x}\right)+\left(\frac{4}{x}\right)\left(\frac{3}{4x}\right)+ \left(\frac{-1}{2x}\right)\left(\frac{2}{3x}\right)+ \left(\frac{-1}{2x}\right)\left(\frac{3}{4x}\right)\)(4/x - 1/2x)/(2/3x+3/4x)
help appreciated
Can you do each of those multiplications?
\(\displaystyle \left(\frac{4}{x}- \frac{1}{2x}\right)\left(\frac{2}{3x}+ \frac{3}{4x}\right)= \left(\frac{4}{x}\right)\left(\frac{2}{3x}\right)+\left(\frac{4}{x}\right)\left(\frac{3}{4x}\right)+ \left(\frac{-1}{2x}\right)\left(\frac{2}{3x}\right)+ \left(\frac{-1}{2x}\right)\left(\frac{3}{4x}\right)\)
Can you do each of those multiplications?
HallsofIvy,
actually there is a division symbol, "/," between the two parenthetical factors. It is a complex fraction, not a product.
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(4/x - 1/2x)/(2/3x+3/4x)
help appreciated
vickycorbett420,
you are missing required grouping symbols.
For example, type it as:
(4/x - 1/(2x))/(2/(3x) + 3/(4x))
Last edited:
HallsofIvy
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Bother!
Then I would do it by combining the fractions in each part.
(4/x - 1/(2x))/(2/(3x)+3/(4x))
4/x- 1/(2x)= 8/(2x)- 1/(2x)= 7/(2x)
2/(3x)+ 3/(4x)= 8/(12x)+ 9/(12x)= 17/(12x)
(7/2x)/(17/12x)= (7/2x)(12x/17)= (7(12x))/(2(17x)
The x terms cancel and 12/2= 6 so this reduces to 42/17.
Then I would do it by combining the fractions in each part.
(4/x - 1/(2x))/(2/(3x)+3/(4x))
4/x- 1/(2x)= 8/(2x)- 1/(2x)= 7/(2x)
2/(3x)+ 3/(4x)= 8/(12x)+ 9/(12x)= 17/(12x)
(7/2x)/(17/12x)= (7/2x)(12x/17)= (7(12x))/(2(17x)
The x terms cancel and 12/2= 6 so this reduces to 42/17.
Bother!
Then I would do it by combining the fractions in each part.
(4/x - 1/(2x))/(2/(3x)+3/(4x))
4/x- 1/(2x)= 8/(2x)- 1/(2x)= 7/(2x)
2/(3x)+ 3/(4x)= 8/(12x)+ 9/(12x)= 17/(12x)
> > > (7/2x)/(17/12x)= (7/2x)(12x/17)= (7(12x))/(2(17x) < < <
HallsofIvy, you got careless in this line. There are missing required grouping symbols.
The x terms cancel and 12/2= 6 so this reduces to 42/17.
Here is a possible amendment:
(7/(2x))/(17/(12x)) = (7/(2x))(12x/17) = (7(12x))/(2(17x))
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