Law of sines
Law of sines: use known side a, opposite angle a, target angle b. Review the formula, worked example and calculation steps.
Inputs
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Formula & explanation
b = a sin B / sin A
Variables & units
- Known side a
- m · minimum 0.000001, maximum 1000000000000
- Opposite angle A
- ° · minimum 0.000001, maximum 179.999999
- Target angle B
- ° · minimum 0.000001, maximum 179.999999
Worked example
a=5 opposite 30°, B=90° gives b=10.
Assumptions
Solves a triangle with two known angles. It does not silently choose a branch in the ambiguous SSA case.
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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