Given P = [pij]3 × 3 and Q = [qij]3 × 3 are 3 × 3 matrices, where qij = 2i + j – 1 pij. If |Q| = 210, then the value of |adj(adj(P))| is
Correct Answer :
Solution :
The correct answer is 16.
Let us solve the problem step-by-step.
We are given two matrices, and , such that:
Let us write the matrix explicitly in terms of the elements of :
Now, let us calculate the determinant of , denoted as :
We can factor out common terms from the rows and columns of this determinant:
From row 1 (), take out a factor of .
From row 2 (), take out a factor of .
From row 3 (), take out a factor of .
This gives:
Next, we can factor out common terms from the columns:
From column 2 (), take out a factor of .
From column 3 (), take out a factor of .
This gives:
Simplifying the powers of 2 and identifying the remaining determinant as :
We are given that . Substituting this value:
Dividing both sides by :
Now, we need to find the value of .
For a matrix of order , we have the standard property:
Here, is a matrix, so .
Substituting and :
Thus, the value of is 16.
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