Factor 6x^2-11x+4 with the AC Method

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The discussion focuses on factoring the quadratic expression 6x^2 - 11x + 4 using the AC method. Participants explore various factor pairs and combinations but initially struggle to find the correct factors. The correct approach involves identifying that the product of the coefficients A (6) and C (4) equals 24, and the factors of 24 that sum to -11 are -3 and -8. Ultimately, the correct factorization is revealed to be (2x - 1)(3x - 4). The conversation emphasizes the importance of correctly applying the AC method for successful factorization.
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Homework Statement


6x^2-11x+4


Homework Equations


none


The Attempt at a Solution


MP
24
6x-2
6x+12

answer being: 6x+2 and x-2
 
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By the trial&error method, for 6x^2 - 11x + 4,
(6x + ?)(x +... you know this one is no good.
(6x - ?)(x - ?)
(2x - ?)(3x - ?)

You get a product of 4 from any of these:
4=4*1=2*2
 


thanks but it has to be an answer in like the form i stated. Or maybe i am just not understanding you...
 


kadavis2010 said:

Homework Statement


6x^2-11x+4


Homework Equations


none


The Attempt at a Solution


MP
24
6x-2
6x+12

answer being: 6x+2 and x-2
Are you saying that the factorization is (6x + 2)(x -2)? Whether you are or aren't, these aren't the factors of 6x^2 -11x + 4.
 


Try the AC method
6x^2-11x+4 coef for A=6; coef for c=4 product 6(4)=24;
find facors of 24 which can make 11 (3 and 8)
hth
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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