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Year 12s: what will be the first way you research your future options? >>

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Help!!!Cosine rule

Help!!!Cosine rule

BOOKWARM

whats cosine rule derivation?

Reply 1

lilyy..p

cosine rule is used when the triangle has no matching pairs.
To find angle:
CosA = b^2 + c^2 - a^2 / 2bc

To find side:
a^2 = b^2 + c^2 - 2bcCosA

* ^ is squared
* / is divide

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