Snowie9
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How to solve an equation with same unknown but different power?
For example this:
12.17=0.036X + 1.9363x10^-8 X^3 -8.756x10^-9X^3 + 1.672x10^-12X^4

The answer is X=296.17
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RDKGames
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(Original post by Snowie9)
How to solve an equation with same unknown but different power?
For example this:
12.17=0.036X + 1.9363x10^-8 X^3 -8.756x10^-9X^3 + 1.672x10^-12X^4

The answer is X=296.17
Use a computer.
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Snowie9
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If I can use a computer to solve it in my exams, I wouldn't be asking here for answers right?
(Original post by RDKGames)
Use a computer.
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RDKGames
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(Original post by Snowie9)
If I can use a computer to solve it in my exams, I wouldn't be asking here for answers right?
Can you use your calculator?

The analytical way is.... wasted effort, to say the least.

Numerical methods are your other option.
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Snowie9
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Isn't the highest degree is 3?
(Original post by Snowie9)
If I can use a computer to solve it in my exams, I wouldn't be asking here for answers right?
(Original post by RDKGames)
Can you use your calculator?

The analytical way is.... wasted effort, to say the least.

Numerical methods are your other option.
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RDKGames
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(Original post by Snowie9)
Isn't the highest degree is 3?
Last term has x^4
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Snowie9
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No? There's a b c d in the 3 degree and I couldn't enter the term without unknown cause I can only enter 4 terms?
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RDKGames
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(Original post by Snowie9)
No? There's a b c d in the 3 degree and I couldn't enter the term without unknown cause I can only enter 4 terms?
3rd degree polynomial means the highest power that occurs in the polynomial is x^3.

You wrote yours as: 12.17=0.036X + 1.9363x10^-8 X^3 -8.756x10^-9X^3 + 1.672x10^-12X^4

The last term has X^4, which is the highest power of X in that equation, therefore the polynomial is a 4th degree one.
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chibichibi_xx
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(Original post by Snowie9)
How to solve an equation with same unknown but different power?
For example this:
12.17=0.036X + 1.9363x10^-8 X^3 -8.756x10^-9X^3 + 1.672x10^-12X^4

The answer is X=296.17
couldn't you use the factor theorem and then algebraic long division?
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Sinnoh
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(Original post by chibichibi_xx)
couldn't you use the factor theorem and then algebraic long division?
You've got a nested polynomial in the index with that last one? There is no way.
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Snowie9
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1.9636x10^2 * my bad. So I couldn't key into calculator cause there's 5 terms in the equation and calculator only allows 4
(Original post by RDKGames)
3rd degree polynomial means the highest power that occurs in the polynomial is x^3.

You wrote yours as: 12.17=0.036X + 1.9363x10^-8 X^3 -8.756x10^-9X^3 + 1.672x10^-12X^4

The last term has X^4, which is the highest power of X in that equation, therefore the polynomial is a 4th degree one.
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RDKGames
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(Original post by Snowie9)
1.9636x10^2 * my bad. So I couldn't key into calculator cause there's 5 terms in the equation and calculator only allows 4
Well I'm kinda lost on this thread at this stage. I even put your equation into Wolfram Alpha and X=296.17 is not a solution.

At this stage I recommend you figure out what went wrong, and where. Once you have the correct equation, check it on wolfram alpha to see that the given answer is indeed a solution, and then we can look at what options there are available for you as far as solving it goes.

https://www.wolframalpha.com/input/?...x10%5E-12X%5E4
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the bear
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(Original post by Sinnoh)
You've got a nested polynomial in the index with that last one? There is no way.
i don't think so.... it is supposed to look like

12.17=0.036X + 1.9363x10-8 X3 - 8.756x10-9X3 + 1.672x10-12X4
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bingbong654
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I get 327.20 and -6828.52?
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Ligretto Cowboy
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Can you check your question again? Because I substituted your stated x value in the equation and I didn’t get zero. So, there must be something wrong with the question.

EDIT
(1.672×10−12×296.174)-(8.756×10−9×296.173)+(1.9363×10−8×296.173)+(0.036×296.17)-12.17 = -1.1391771.... ≉0
Last edited by Ligretto Cowboy; 3 months ago
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