Problem:
For real numbers a and b, define a⋄b=a2+b2​. What is the value of
(5⋄12)⋄((−12)⋄(−5))?
Answer Choices:
A. 0
B. 217​
C. 13
D. 132​
E. 26
Solution:
It follows from the definition that
(5⋄12)⋄((−12)⋄(−5))​=52+122​⋄(−12)2+(−5)2​=13⋄13=132+132​=132​​
Answer: D​.
The problems on this page are the property of the MAA's American Mathematics Competitions