Revision:Sine and Cosine Formulae

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Sine and Cosine Formulae

e.g.

The Sine Rule

This works in any triangle:

alternatively:

NOTE: the triangle is labelled as follows:

(diagram of the labelled triangle is missing)

The Cosine Rule

can also be written as:

This also works in any triangle.

The area of a triangle

This works out the area of any triangle.

(using the above notation)

This formula is useful if you don't know the height of a triangle (since you need to know the height for the formula).

Comments

Thia article is missing diagrams.