Multiplying Fractions: Simplifying with GCF

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Homework Statement


I would just like to know if I got this right. ((x2 + 2x + 1)/(18cw3) times ((12c3w)/(x2 - 1)) = (12c3wx2 + 2x12c3w + 12c3w)/(18cw3)(x2 - 18cw3

Homework Equations


((x2 + 2x + 1)/(18cw3) times ((12c3w)(x2 - 1))

The Attempt at a Solution


(12c3wx2 + 2x12c3w + 12c3w)/((18cw3)(x2 - 1)) = (12c3wx2 + 2x12c3w + 12c3w)/(18cw3x2 - 18cw3
 
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I accidentally used a subscript all the way through instead of a power, argh!
 
science_rules said:
##(12c_3wx_2 + 2x12c_3w + 12c_3w)/(18cw_3x_2 - 18cw_3##
On the right side one of the terms is ##2x12c_3w##. Should that have been ##2x^{12}c^3##? Also, you're missing a right parenthesis.
 
Mark44 said:
On the right side one of the terms is ##2x12c_3w##. Should that have been ##2x^{12}c^3##? Also, you're missing a right parenthesis.
It should have been as haruspex said: (x2 + 2x + 1)/(18cw3) times (12c3w)/(x2-1)
 
haruspex said:
Do you mean ##\frac{x^2+2x+1}{18cw^3}\frac{12c^3w}{x^2-1}##?
If so, there is a lot of cancellation available. Factorise the two expressions involving x.
Yes, that is what I meant.
 
science_rules said:
Yes, that is what I meant.
haruspex said:
Do you mean ##\frac{x^2+2x+1}{18cw^3}\frac{12c^3w}{x^2-1}##?
If so, there is a lot of cancellation available. Factorise the two expressions involving x.
(x+1)(x+1)/(18cw3) times (12c3w)/(x-1)(x+1)
The x+1 cancels, leaving: (x+1)/(18cw3) times (12c3w)/(x-1)
 
haruspex said:
More cancellation to go. Look at the constants, look at the powers of c and w.
(x+1)/((3w)(6cw2)) times ((3w)(4c3))/(x-1) = (x+1)/(6cw2) times (4c3)/(x-1)
 
science_rules said:
(x+1)/((3w)(6cw2)) times ((3w)(4c3))/(x-1) = (x+1)/(6cw2) times (4c3)/(x-1)
The 3w is canceled
 
science_rules said:
The 3w is canceled
I meant that 3wc is canceled, leaving: (x+1)/(w2) times (4c2)/(x-1)
 
haruspex said:
You made a mistake with the constants.
Should it be: 3cw(w2) and 3cw(4c2)??
 
science_rules said:
Should it be: 3cw(w2) and 3cw(4c2)??
Oops I meant: 3cw(6w2) and 3cw(4c2)
 
haruspex said:
Yes.
Thank you for your help
 
haruspex said:
Yes.
So the answer is: (x+1)/(6w2) times (4c2)/(x-1)
 
science_rules said:
(x+1)/((3w)(6cw2)) times ((3w)(4c3))/(x-1) = (x+1)/(6cw2) times (4c3)/(x-1)

science_rules said:
The 3w is canceled

science_rules said:
I meant that 3wc is canceled, leaving: (x+1)/(w2) times (4c2)/(x-1)

science_rules said:
Should it be: 3cw(w2) and 3cw(4c2)??

science_rules said:
Oops I meant: 3cw(6w2) and 3cw(4c2)
Instead of adding new posts each time you discover something you should have said, you can edit the post you want to change.
 
science_rules said:
So the answer is: (x+1)/(6w2) times (4c2)/(x-1)
The constants can be further simplified, and then you should bring it together so you have one fraction.
 
Thewindyfan said:
The constants can be further simplified, and then you should bring it together so you have one fraction.
Like this?: (x+1)/(6w2) times (4c2)/(x-1) = 4c2x + 4c2/6w2x-6w2 = 2c(2cx+2c)/2w(3wx-3w)<------(Answer)?
 
science_rules said:
Like this?: (x+1)/(6w2) times (4c2)/(x-1) = 4c2x + 4c2/6w2x-6w2 = 2c(2cx+2c)/2w(3wx-3w)<------(Answer)?
1)
Thewindyfan said:
The constants can be further simplified
2) I think you can leave the nominator as ##2c²(x+1)##, and similarly for the denominator. Certainly would give a better readable result.
 
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Samy_A said:
1)

2) I think you can leave the nominator as ##2c²(x+1)##, and similarly for the denominator. Certainly would give a better readable result.
How did you get 2c2(x+1) when it was 4c2/(x+1)?? Isn't the numerator supposed to be 2c2(2x+2)??
And the denominator is supposed to be: 2w2(3x-3)??
 
science_rules said:
How did you get 2c2(x+1) when it was 4c2/(x-1)?? Isn't the numerator supposed to be 2c2(2x+2)??
And the denominator is supposed to be: 2w2(3x-3)??
You are still not doing all the simplification you could. In what you posted above, each parenthetic term has a factor that can be taken outside. Having done that, one of the primes occurs above and below the line.
 
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haruspex said:
You are still not doing all the simplification you could. In what you posted above, each parenthetic term has a factor that can be taken outside. Having done that, one of the primes occurs above and below the line.
Okay, I think I have it now: (x2 + 2x + 1)/(18cw3) times (12c3w)/(x2-1) = (x+1)2(12c3w)/(18cw2)(x+1)(x-1) Cancel the (x+1) = (12c3w)(x+1)/(18cw2)(x-1) Cancel the c and w = (12c2)(x+1)/(18w)(x-1) divided by 3 (numerator and denominator) = (4c2)(x+1)/(6w)(x-1) divided by 2 (numerator and denominator) = (2c2)(x+1)/(3w)(x-1) Answer
 
science_rules said:
Okay, I think I have it now: (x2 + 2x + 1)/(18cw3) times (12c3w)/(x2-1) = (x+1)2(12c3w)/(18cw2)(x+1)(x-1) Cancel the (x+1) = (12c3w)(x+1)/(18cw2)(x-1) Cancel the c and w = (12c2)(x+1)/(18w)(x-1) divided by 3 (numerator and denominator) = (4c2)(x+1)/(6w)(x-1) divided by 2 (numerator and denominator) = (2c2)(x+1)/(3w)(x-1) Answer
Enclose the entire denominator in parentheses.
(2c2)(x+1)/((3w)(x-1)) .
 
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science_rules said:
Okay, I think I have it now: (x2 + 2x + 1)/(18cw3) times (12c3w)/(x2-1) = (x+1)2(12c3w)/(18cw2)(x+1)(x-1) Cancel the (x+1) = (12c3w)(x+1)/(18cw2)(x-1) Cancel the c and w = (12c2)(x+1)/(18w)(x-1) divided by 3 (numerator and denominator) = (4c2)(x+1)/(6w)(x-1) divided by 2 (numerator and denominator) = (2c2)(x+1)/(3w)(x-1) Answer
You could've reached the last step by recognizing that 6 is the GCF for the numerator and denominator.