Difference between revisions of "1998 AHSME Problems/Problem 17"

(Problem)
(Undo revision 217553 by Gaurishasagar (talk))
(Tag: Undo)
 
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: (b) <math>f(0) = 2</math>.
 
: (b) <math>f(0) = 2</math>.
  
What is the value of <math>f(2021)</math>?
+
What is the value of <math>f(1998)</math>?
  
 
<math>\mathrm{(A)}\ 0  
 
<math>\mathrm{(A)}\ 0  
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\qquad\mathrm{(C)}\ 1996
 
\qquad\mathrm{(C)}\ 1996
 
\qquad\mathrm{(D)}\ 1998  
 
\qquad\mathrm{(D)}\ 1998  
\qquad\mathrm{(E)}\ 2000</math>
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\qquad\mathrm{(E)}\ 2000</math>  
 
 
 
== Solution ==
 
== Solution ==
 
<cmath>f(1998 + 0) = 1998 + f(0) = 2000 \Rightarrow \mathrm{(E)}</cmath>
 
<cmath>f(1998 + 0) = 1998 + f(0) = 2000 \Rightarrow \mathrm{(E)}</cmath>

Latest revision as of 21:16, 28 March 2024

Problem

Let $f(x)$ be a function with the two properties:

(a) for any two real numbers $x$ and $y$, $f(x+y) = x + f(y)$, and
(b) $f(0) = 2$.

What is the value of $f(1998)$?

$\mathrm{(A)}\ 0  \qquad\mathrm{(B)}\ 2  \qquad\mathrm{(C)}\ 1996 \qquad\mathrm{(D)}\ 1998  \qquad\mathrm{(E)}\ 2000$

Solution

\[f(1998 + 0) = 1998 + f(0) = 2000 \Rightarrow \mathrm{(E)}\]

The function $f(x) = x+2$ satisfies these properties.

See also

1998 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 16
Followed by
Problem 18
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

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