Difference between revisions of "1966 AHSME Problems/Problem 33"

(Solution)
(Solution 2)
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== Solution 2 ==
 
== Solution 2 ==
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Let <math>m=\frac{x-a}{b}</math> and <math>n=\frac{x-b}{a}</math> then we have
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<cmath>m+n=\frac{1}{m}+\frac{1}{n}</cmath>
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<cmath>m+n=\frac{m+n}{mn}</cmath>
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Notice that the equation is possible iff <math>m+n=0</math> or <math>mn=1</math>.
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If <math>m+n=0</math> then
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<math></math>\frac{
  
 
== See also ==
 
== See also ==

Revision as of 18:34, 23 December 2019

Problem

If $ab \ne 0$ and $|a| \ne |b|$, the number of distinct values of $x$ satisfying the equation

\[\frac{x-a}{b}+\frac{x-b}{a}=\frac{b}{x-a}+\frac{a}{x-b},\]

is:

$\text{(A) zero}  \quad \text{(B) one}  \quad \text{(C) two}  \quad \text{(D) three}  \quad \text{(E) four}$

Solution

$\fbox{D}$

Solution 2

Let $m=\frac{x-a}{b}$ and $n=\frac{x-b}{a}$ then we have \[m+n=\frac{1}{m}+\frac{1}{n}\] \[m+n=\frac{m+n}{mn}\] Notice that the equation is possible iff $m+n=0$ or $mn=1$.

If $m+n=0$ then $$ (Error compiling LaTeX. Unknown error_msg)\frac{

See also

1966 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 32
Followed by
Problem 34
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
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