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Let A =a_ i j be a matrix of order 3 where a_ i j = [ array ll x & if i=j, x R 1 & if |i-j|=1 0 & otherwise array . then which of the following hold(s) good?

Options

  1. AFor x=2, A is a diagonal matrix.
  2. BA is a symmetric matrix.
  3. CFor x=2, det A has the value equal to 6
  4. DLet f ( x )= det A , then the function f ( x ) has both the maxima and minima

Correct answer

D. Let f ( x )= det A , then the function f ( x ) has both the maxima and minima

Step-by-step solution

A= [ array ccc x & 1 & 0 1 & x & 1 0 & 1 & x array ] ; x (x^2-1 )-1(x)=6-2=4

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