System of Equations: Solving U & V with Polynomials

AI Thread Summary
The discussion focuses on solving a system of equations involving variables U and V. The provided equations are simplified to isolate U and V, leading to the solutions U=(s+1)/s^2 and V=(2s+1)/s^2. A participant struggles with complicated polynomials and seeks guidance on a general approach to solving such equations. They suggest using elimination and restructuring the equations for clarity. The conversation emphasizes the importance of showing work for effective assistance.
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Homework Statement



sU-1+U-V=0
sV-2-U+V=(2/s)

Homework Equations


N/A

The Attempt at a Solution


the solutions are
U=(s+1)/s^2

V=(2s+1)/s^2

but I just keep getting complicated polynomials that I don't seem to be able to factor.

If someone could show me how this particular one was done and what a general approach is I would greatly appreciate it.
 
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I was able to get the answers you posted. It may help to "clean" up the equations so that there is only one U and one V shown in each on the LHS, like this:

\begin{aligned}<br /> (s+1)U - V &amp;= 1 \\<br /> -U + (s+1)V &amp;= (2/s) + 2<br /> \end{aligned}

I used elimination by multiplying eq. 1 by s+1 and adding to eq. 2 to eliminate the V. In any event you have to show your work first, so either show us what you've got or try what I did, and we'll check it for you.
 
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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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