WEBVTT

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As a hint, I'll take the determinant of a very similar two by two matrix.

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So we wanna figure out the determinant of this matrix and we can denote it

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by the determinant of the 2x2 matrix five,

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three,negative one and four

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and the definition of determinant of the 2x2 matrix like this, as we can first take

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this diagonal, five times four

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so write it down, just going to be equal to

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5 * 4 minus of product of that diagonal

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...so what is this

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give us? So, five times four is twenty

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and then three times negative one will be negative three

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this is negative three...

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but making negative the negative three will make the positive three

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so the determinant of this matrix is twenty three.