Difference between revisions of "1958 AHSME Problems/Problem 4"

(Solution)
(Solution)
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==Solution==
 
==Solution==
  
When <math> x=\dfrac{1}{2}</math>, <math> \dfrac{x+1}{x-1}=-3</math>, substituting <math> -3</math> for <math> x</math> in the original equation we get:
+
When <math> x=\frac{1}{2}</math>, <math> \frac{x+1}{x-1}=-3</math>, substituting <math> -3</math> for <math> x</math> in the original equation we get:
  
<math> \dfrac{-3+1}{-3-1}=\dfrac{-2}{-4}=\dfrac{1}{2}\implies \boxed{\mathbf{(E)}\text{ None of these}}</math>.
+
<math> \frac{-3+1}{-3-1}=\frac{-2}{-4}=\frac{1}{2}\implies \boxed{\mathbf{(E)}\text{ None of these}}</math>.
  
 
==See also==
 
==See also==
  
 
{{AHSME box|year=1958|num-b=3|num-a=5}}
 
{{AHSME box|year=1958|num-b=3|num-a=5}}

Revision as of 13:14, 4 June 2011

Problem

In the expression $\frac{x + 1}{x - 1}$ each $x$ is replaced by $\frac{x + 1}{x - 1}$. The resulting expression, evaluated for $x = \frac{1}{2}$, equals:

$\textbf{(A)}\ 3\qquad  \textbf{(B)}\ -3\qquad  \textbf{(C)}\ 1\qquad  \textbf{(D)}\ -1\qquad  \textbf{(E)}\ \text{none of these}$

Solution

When $x=\frac{1}{2}$, $\frac{x+1}{x-1}=-3$, substituting $-3$ for $x$ in the original equation we get:

$\frac{-3+1}{-3-1}=\frac{-2}{-4}=\frac{1}{2}\implies \boxed{\mathbf{(E)}\text{ None of these}}$.

See also

1958 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 3
Followed by
Problem 5
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
All AHSME Problems and Solutions