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$$\frac{x^3-49x}{ x^4-13x^3+50x^2-56x}$$

I get answer $\frac {x+3} {x-1}$ but my friend say it's wrong I dont understand please help me please

greetings from russia

Vladimir
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  • This is not a differential equation! – Jan Eerland Sep 28 '16 at 17:09
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    How did you get the answer? –  Sep 28 '16 at 17:10
  • What are exactly the paranthesis and the division bar ? See this in both case : http://www.wolframalpha.com/input/?i=x%5E3-49x+%2F+(x%5E4-13x%5E3%2B50x%5E2-56x) http://www.wolframalpha.com/input/?i=(x%5E3-49x)+%2F+(x%5E4-13x%5E3%2B50x%5E2-56x) – Zubzub Sep 28 '16 at 17:10
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    Hint: try substituting $x = 10$. Your answer gives $13/9$, whereas the original expression equals $17/48$. – Santiago Sep 28 '16 at 17:16

1 Answers1

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$$\frac{x^3-49x} { (x^4-13x^3+50x^2-56x)}=\frac{x(x^2-49)}{x(x^3-13x^2+50x-56)}=\frac{x(x-7)(x+7)}{x(x-2)(x-4)(x-7)}$$

E.H.E
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