Let . If for some , then is equal to
Answer: 24
Solution
Matrix A is upper triangular. By induction, .
From : and .
So . Substituting: , ✓.
Also, . Substituting and :
, so .
From , . So , giving .
Solving: , , , .
Then , . So .
From : and .
So . Substituting: , ✓.
Also, . Substituting and :
, so .
From , . So , giving .
Solving: , , , .
Then , . So .
JEE Main · 2022 · 25 Jul 2022 · Shift 2 · Integer answer