ExamBro
ExamBro
JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant

Let \(P = \left[ {\begin{array}{*{20}{c}}
  1&0&0 \\ 
  3&1&0 \\ 
  9&3&1 
\end{array}} \right]\) and \(Q = [q_{ij}]\) be two \(3\times3\) matrices such that \(Q -P^5 = I_3\). Then \(\frac{{{q_{21}} + {q_{31}}}}{{{q_{32}}}}\) is equal to

  1. A \(10\)
  2. B \(135\)
  3. C \(15\)
  4. D \(9\)
Verified Solution

Answer & Solution

Correct Answer

(A) \(10\)

Step-by-step Solution

Detailed explanation

\({P^2} = \left[ {\begin{array}{*{20}{c}} 1&0&0\\ 6&1&0\\ {24}&6&1 \end{array}} \right]{P^3} = \left[ {\begin{array}{*{20}{c}} 1&0&0\\ 9&1&0\\ {54}&9&1 \end{array}} \right].\therefore {P^5} = \left[ {\begin{array}{*{20}{c}} 1&0&0\\ {15}&1&0\\ {135}&{15}&1 \end{array}} \right]\)…
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app