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Here is a tricky one to keep you busy while waiting for the AP to announce the election results...
Can you solve the following system of equations for real variables x, y and z
\begin{cases}
\frac{x}{1 + a} + \frac{y}{2 + a} + \frac{z}{3 + a} = 1 \\
\frac{x}{1 + b} + \frac{y}{2 + b} + \frac{z}{3 + b} = 1 \\
\frac{x}{1 + c} + \frac{y}{2 + c} + \frac{z}{3 + c} = 1
\end{cases}
where a, b and c are distinct real numbers?
Previous iteration: #753021 (visual and written answers in #753251 and #753272, respectively).
x = A(1+a)(1+b)(1+c)
y = B(2+a)(2+b)(2+c)
z = C(3+a)(3+b)(3+c)
\frac{x}{1+a} + \frac{y}{2+a} + \frac{z}{3+a}
=A(1+b)(1+c) + B(2+b)(2+c) + C(3+b)(3+c)
=A(1+b+c+bc) + B(4+2b+2c+bc) + C(9+3b+3c+bc)
All that has to equal to 1, so we get a system of equations:
A + 4B + 9C = 1
A + 2B + 3C = 0
A + B + C = 0
Which if we solve gives us: A=0.5, B=-1, C=0.5.
By symmetry it's easy to show that this solutions works for all three of the above equations.
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I'm not a mathematician, but if I studied it maybe I could understand it a little.
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Never too late~~
You can click through to earlier iterations, I've posted easier ones that rely on some logical reasoning rather than equations.
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That's right, I also want to be good at mathematics, I have to try and not be late in learning mathematics.
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I don't want to spoil anyone's fun, but the answer is pretty obvious on this one....
I'm pretty sure you know that I know. 😏
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I'm only 42% sure.
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