Find the integral value of x, if



Expanding along the first row



= x2(2×4 – 1×1) – x(0×4 – 1×3) + 1(0×1 – 2×3)


= x2(8 – 1) – x(0 – 3) + 1(0 – 6)


= 7x2 + 3x –6


Also |A| = 28


7x2 + 3x – 6 =28


7x2 + 3x – 34 = 0


7x2 + 17x – 14x – 34 = 0


x(7x+ 17) – 2(7x +17) = 0


(x–2)(7x +17) = 0



Integer value of x is 2.


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