Evaluate by two methods.


I. Expanding along the first row



= 2(1×1 – 4×(–2)) – 3(7×1 – (–2)×(–3)) – 5(7×4 – 1×(–3))


= 2(1 + 8) – 3(7 – 6) – 5(28 + 3)


= 2×9 – 3×1 – 5×31


= 18 – 3 – 155


= –140


II. Expanding along the second column



= 2(1×1 – 4×(–2)) – 7(3×1 – 4×(–5)) – 3(3×(–2) – 1×(–5))


= 2(1 + 8) – 7(3 + 20) – 3(–6 + 5)


= 2×9 – 7×23 – 3×(–1)


= 18 – 161 +3


= –140


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