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What is the value of $$\frac{2013^3-2\cdot 2013^2\cdot 2014+3\cdot 2013\cdot 2014^2-2014^3+1}{2013\cdot 2014}?$$


What I have tried:

$$\implies\frac{2013^2(2013-2\cdot2014)+2014^2(3\cdot 2013-2014)+1}{2013\cdot 2014}$$ $$\implies\frac{2013^2(-2015)+2014^2(4025)+1}{2013\cdot 2014}$$

I'm not sure what to do next...

Help is appreciated!

Furthermore, if you are nice, could you also help me on this problem(Transferring bases of numbers.) too?

Thanks!

Max0815

Blue
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Max0815
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4 Answers4

3

You can complete the cube of the difference.

$$ =\frac{2013^3-3\cdot2013^2\cdot2014+3\cdot2013\cdot2014^2-2014^3+2013^2\cdot2014+1}{2013\cdot2014} $$ $$ =\frac{(2013-2014)^3+2013^2\cdot2014+1}{2013\cdot2014}=\frac{2013^2\cdot2014}{2013\cdot2014}=2013 $$

GReyes
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1

$$= \frac {(2013-2014)^3+2013^2\cdot 2014+1}{2013\cdot 2014}$$

$$=\frac {-1+2013^2\cdot 2014+1}{2013\cdot 2014}$$

$$=2013$$

J. W. Tanner
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1

Hint

Choose $2013=a$

$$\dfrac{a^3-2a^2(a+1)+3a(a+1)^2-(a+1)^3+1}{a(a+1)}$$

$$=\dfrac{-3a(a+1)+a(a+1)\{3(a+1)-2a\}}{a(a+1)}$$

$$=-3+3+a$$ as $a(a+1)\ne0$

1

HINT:

Let $a=2013$ and $b=2014$. You have:

$$\frac{a^3 - 2a^2b + 3ab^2 - b^3 + 1}{ab}$$

Recall that $(a-b)^3=a^3-3a^2b+3ab^2-b^3$ and use that to simplify.

Rhys Hughes
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