Evaluation Of a Third-Order Determinant

in Mathematics4 years ago

Good morning and welcome to today's Mathematics class.

Today we shall be looking at Evaluation of a third-order determinant.

To expand a Determinant of the third order, we can write down each element along the the top row, multiply it by its minor and give the terms a plus or minua sign alternately:

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Example1: expand the determinant by expanding the top row.

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Example2: Expand the determinant by expanding the middle column.

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Example 3: Evaluate the determinant by expanding along the bottom row.

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Example 4: Evaluate the determinant by expanding along the middle row.

IMG_20200821_120621_9~2.jpg

In the next class
We shall be looking at Method to solve simultaneous Equations in 3 unknowns.

Thanks for staying with us.
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https://hive.blog/hive-122481/@mbietanie/angles-in-a-polygon