Difference between revisions of "1967 AHSME Problems/Problem 14"

(Solution)
(Solution)
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Since we know that <math>y=f(x)</math>, we can solve for <math>y</math> in terms of <math>x</math>. This gives us
 
Since we know that <math>y=f(x)</math>, we can solve for <math>y</math> in terms of <math>x</math>. This gives us
  
<cmath>y=\frac{1}{1-x}\RightArrow y(1-x)=1 \RightArrow y-yx=1\RightArrow yx=y-1\RightArrow x=\frac{y-1}{y}</cmath>
+
/[y=\frac{1}{1-x}\RightArrow y(1-x)=1 \RightArrow y-yx=1\RightArrow yx=y-1\RightArrow x=\frac{y-1}{y}[/
  
 
== See also ==
 
== See also ==

Revision as of 13:10, 10 August 2020

Problem

Let $f(t)=\frac{t}{1-t}$, $t \not= 1$. If $y=f(x)$, then $x$ can be expressed as

$\textbf{(A)}\ f\left(\frac{1}{y}\right)\qquad \textbf{(B)}\ -f(y)\qquad \textbf{(C)}\ -f(-y)\qquad \textbf{(D)}\ f(-y)\qquad \textbf{(E)}\ f(y)$

Solution

Since we know that $y=f(x)$, we can solve for $y$ in terms of $x$. This gives us

/[y=\frac{1}{1-x}\RightArrow y(1-x)=1 \RightArrow y-yx=1\RightArrow yx=y-1\RightArrow x=\frac{y-1}{y}[/

See also

1967 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 13
Followed by
Problem 15
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