How Do You Solve a Fourth-Degree Polynomial Temperature Model?

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The discussion revolves around solving a fourth-degree polynomial temperature model based on limited data points. The user initially assumed the polynomial form and calculated coefficients, but received feedback indicating their answer was incorrect. It was clarified that the problem required the answer to be presented as a product of linear factors rather than a fully expanded polynomial. The correct format is to maintain the expression as (1/1152)x(x-10)(x-16)(x-24). The confusion stemmed from misinterpretation of the instructions regarding the format of the answer.
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This is one of my homework problems:
"A scientist has limited data on the temperature T during a 24-hour period. If t denotes time in hours and t = 0 corresponds to midnight, find the fourth-degree polynomial that fits the information in the following table.

t (hours) 0 10 12 16 24
T (celcius) 0 0 1 0 0

Please enter your answer as a product of linear factors. Enter any fractions or fractional coefficients as fractions, not as decimals."


I assumed the form was : T(t) = ax(x-10)(x-16)(x-24)
I found 'a' by using the given T(12)=1 and got: a = 1/1152
Multiplying out the factors i got:
T(t) = 1/1152*x^4 - 25/576*x^3 + 49/72*x^2 - 10/3*x

I'm confused as to why the program says this is the wrong answer. Maybe i have some faulty arithmetic...Any ideas?
 
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looks fine to me *shrug*
 
looks like (1/1152)x(x-10)(x-16)(x-24) worked even though it said to multiply it out...thanks anyways
 
yeah, that makes a lot of sense looking at the problem again

"Please enter your answer as a product of linear factors."
means that you keep it exactly as it was when it marked it correct.

x, x-10, x-16, x-24 were our linear factors, so we'd just write it as their product:

\frac{1}{1152}x(x-10)(x-16)(x-24)
 
Tzz said:
looks like (1/1152)x(x-10)(x-16)(x-24) worked even though it said to multiply it out...thanks anyways
WHERE did it say "multiply it out"?
 
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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