Evaluate `|2 3-5 7 1-2-3 4 1|` by two methods.

Explanation

`|(2, 3,-5 ),(7, 1,-2),(-3 ,4 ,1)|`

Then we expanding along `1^(st)` row we get

`=2(1+8)−3(7−6)−5(28+3)`

`=18−3−155`

`=−140`

Second method

Now we expanding along `1^(st)` column we get

`= 2(1xx1 – 4xx(–2)) – 7(3xx1 – 4xx(–5)) – 3(3xx(–2) – 1xx(–5))`

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