Difference between revisions of "2000 AMC 12 Problems/Problem 11"

(New page: ==Problem== Two non-zero real numbers, <math>a</math> and <math>b,</math> satisfy <math>ab = a - b</math>. Which of the following is a possible value of <math>\frac {a}{b} + \frac {b}{a} -...)
 
Line 5: Line 5:
  
 
==Solution==
 
==Solution==
{{solution}}
+
[[WLOG]], let a=1. Solving for b, we have b=1/2, and <math>\frac {a}{b} + \frac {b}{a} - ab=2\Rightarrow \text{(E)}</math>
  
 
==See Also==
 
==See Also==
 +
{{AMC12 box|year=2000|num-b=10|num-a=12}}
 +
 +
[[Category:Introductory Algebra Problems]]

Revision as of 14:25, 3 January 2008

Problem

Two non-zero real numbers, $a$ and $b,$ satisfy $ab = a - b$. Which of the following is a possible value of $\frac {a}{b} + \frac {b}{a} - ab$?

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

Solution

WLOG, let a=1. Solving for b, we have b=1/2, and $\frac {a}{b} + \frac {b}{a} - ab=2\Rightarrow \text{(E)}$

See Also

2000 AMC 12 (ProblemsAnswer KeyResources)
Preceded by
Problem 10
Followed by
Problem 12
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
All AMC 12 Problems and Solutions