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Question
Without expanding, evaluate the following determinants:
`|(2, 3, 4),(5, 6, 8),(6x, 9x, 12x)|`
Solution
`|(2, 3, 4),(5, 6, 8),(6x, 9x, 12x)| = x|(2, 3, 4),(5, 6, 8),(6, 9, 12)|`
= `(x)(3)|(2, 3, 4),(5, 6, 8),(2, 3, 4)|`
= 3x (0)
= 0
∴ R1 = R2
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