Trigonometry · Classes 11, 12
Cosine Rule
Find third side using included angle.
FORMULA
\(c^2=a^2+b^2-2ab\cos C\)
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Enter values to see a result and calculation steps.
Worked example
a=3,b=4,C=90° ⇒ c=5
Understand this formula
Find third side using included angle.
Check measurement units, mathematical domains and rounding before applying any result in an examination.