For some , let and be such that . Then is equal to:
JEE Mathematics 2026 Question with Solution
Answer
Correct answer:50625
Step-by-step solution
Standard Method
Given:
- The stated matrix relation is interpreted in the solution as
Find: .
The extracted solution itself states that the question is flawed and leads to a contradiction, so the published numerical answer is obtained only after assuming an intended corrected problem.
Compute the left-hand side:
Hence,
Compute the right-hand side:
So,
Equating corresponding entries gives:
and
Now check the entry:
while
Since
the given relation is inconsistent.
The published solution therefore assumes an intended corrected result:
Let
Then
For a matrix,
Therefore,
and the required value is
So, using the assumed intended correction from the published solution, the answer is .
Why the Published Answer Requires an Assumption
Given: the extracted solution explicitly notes that the original question statement is contradictory.
Find: why the answer cannot be obtained directly from the printed relation.
The source question text has
which simplifies to
Using the displayed forms of and , entrywise comparison gives incompatible values. That means there is no real pair satisfying all entries simultaneously.
Because of this contradiction, the numerical result is not derivable from the printed equation alone. The extracted solution works backward from the official answer and assumes the intended outcome was
Under that assumption,
and for a matrix,
Hence,
Common mistakes
Using the printed matrix equation without checking consistency is a mistake. Entrywise comparison gives contradictory conditions on and . Always verify all four entries before proceeding to determinant calculations.
Applying incorrectly is a common error. For a matrix, this becomes , not .
Confusing with is incorrect. For a matrix, . So if , then , not .
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