Basic Maths - Grand Test 1 -Q15

+2 votes

The non-integer value of x for which the matrix \begin{bmatrix} 2x-1 & 3&3\\ 3 & 2x-1 & 3\\ 3 & 3 &2x-1 \end{bmatrix} singular is ___

asked Jun 21 in Basic Maths by gbeditor (21,290 points)
reshown Jun 23 by gbeditor

3 Answers

+1 vote
-2.5 is correct one.
answered Jun 23 by tsnikhilsharmagate2018 (24,690 points)
+1 vote

-2.5 is correct one

answered Jun 23 by tsnikhilsharmagate2018 (24,690 points)
In the final result, answer -2.5 showing incorrect.
Is it still showing it as incorrect?
Yupp...  Pls correct it
0 votes

\begin{bmatrix} 2x-1 &3 &3 \\ 3& 2x-1 &3 \\ 3&3 & 3x-1 \end{bmatrix}

C_1\leftarrow C_1+C_2+C_3

\begin{bmatrix} 2x-1+6 &3 &3 \\ 2x-1+6&2x-1 &3 \\ 2x-1+6& 3 & 2x-1 \end{bmatrix}

(2x+5)\begin{bmatrix} 1 &3 &3 \\ 1& 2x-1 & 3\\ 1& 3 & 2x-1 \end{bmatrix}

R_3\leftarrow R_3 - R_2, R_2\leftarrow R_2 - R_1

(2x+5)\begin{bmatrix} 1 &3 &3 \\ 0& 2x-4 & 0\\ 0& 4-2x & 2x-4 \end{bmatrix}

(2x+5)(2x-4)^2

For singular Matrix should be zero

so, x = -2.5 or 2

answered Jun 26 by 23rishiyadavpro20 (6,630 points)
Answer:
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