What is exactly the MO when it comes to solving a quadratic equation like $x^2 + \sqrt{2}\,x - 3$? Do I take the part with the under root to the other side and end up with $x^4$?
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4Do you mean $ x^2 + \sqrt{2}x - 3=0$? Otherwise it is not an equation and there is nothing to solve. – M47145 Jun 05 '16 at 21:51
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5Is the second term $x\sqrt{2}$ or $\sqrt{2x}$? – John_dydx Jun 05 '16 at 21:52
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- You have not answered the question of @John 2) You have to place an $=0$ 3) Thank you, I have learned a new acronym MO (modus operandi) but why not the good old "method"...
– Jean Marie Jun 05 '16 at 22:05 -
IconrrigiblePenguin A clarification would be nice. – callculus42 Jun 05 '16 at 22:12
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If it is a quadratic, then the middle term should be interpreted as $\sqrt{2},x$ and not as $\sqrt{2x}$. – egreg Jun 05 '16 at 22:23
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If you are solving $x^2+x\sqrt 2-3=0$ the quadratic formula works just fine. You get $$x=\frac 12\left(-\sqrt 2\pm\sqrt{2+12}\right)=\frac 12(\pm\sqrt{14}-\sqrt 2)$$ The fact that there is a square root on the linear term is not an issue.
Ross Millikan
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