2021 JMPSC Invitationals Problems/Problem 4
Contents
[hide]Problem
Let and be sequences of real numbers such that , , and, for all positive integers ,
Find .
Solution
We notice that Since we are given that and , we can plug these values in to get that
Similarly, we conclude that
Adding and gives us Dividing both sides by yields
~mahaler
Solution 2
Add both equations to get , and subtract both equations to get , so now we bash: and . and . and . and ,
~Geometry285
See also
- Other 2021 JMPSC Invitationals Problems
- 2021 JMPSC Invitationals Answer Key
- All JMPSC Problems and Solutions
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