Difference between revisions of "1974 AHSME Problems/Problem 6"
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{{AHSME box|year=1974|num-b=5|num-a=7}} | {{AHSME box|year=1974|num-b=5|num-a=7}} | ||
+ | [[Category:Introductory Algebra Problems]] |
Revision as of 10:17, 30 May 2012
Problem
For positive real numbers and
define
' then
Solution
First, let's check for commutivity. We have , so
is commutative.
Now we check for associativity. We have Also,
and so
is also associative.
See Also
1974 AHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 5 |
Followed by Problem 7 | |
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 |