2007 Cyprus MO/Lyceum/Problem 8

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Problem

If we subtract from $2$ the inverse number of $x-1$, we get the inverse of $x-1$. Then the number $x+1$ equals to

$\mathrm{(A) \ } 0\qquad \mathrm{(B) \ } 1\qquad \mathrm{(C) \ } -1\qquad \mathrm{(D) \ } 3\qquad \mathrm{(E) \ } \frac{1}{2}$

Solution

$2-\frac1{x-1}=\frac1{x-1}$


$2=\frac2{x-1}$

Multiplying out and solving, we get that $x = 2$, so $x+1=3\Longrightarrow\mathrm{ D}$.

See also

2007 Cyprus MO, Lyceum (Problems)
Preceded by
Problem 7
Followed by
Problem 9
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