Triangle area · two sides & angle

Triangle area · two sides & angle: use side a, side b, included angle. Review the formula, worked example and calculation steps.

Inputs

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RESULT
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Formula & explanation
A = ½ab sin C

Variables & units

Side a
m · minimum 0, maximum 1000000000000
Side b
m · minimum 0, maximum 1000000000000
Included angle
° · minimum 0.000001, maximum 179.999999

Worked example

Sides 3 and 4 with included angle 90° give area 6.

Assumptions

Use the included angle, not another angle of the triangle.

Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.

Practice with an example

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