Description
Require angleDegrees strictly between zero and 180 and return 90-angle/2 in degrees.
Triangle identities relate side lengths, angles, and special points under a nondegenerate geometric model. A contribution to a point or a local ratio is different from constructing the complete point or proving that supplied values form a triangle.
Require angleDegrees strictly between zero and 180 and return 90-angle/2 in degrees.
When to use this tool
Use Triangle Excentral Angle From Internal when you need an explicit triangle identity or local construction.
How to use the tool and how it works
- Enter angleDegrees. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read excentralAngleDegrees. Use the output convention below.
Require angleDegrees strictly between zero and 180 and return 90-angle/2 in degrees.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| angleDegrees | Angle Degrees | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| excentralAngleDegrees | Excentral Angle Degrees | Required. Finite number. |
{
"input": {
"angleDegrees": 60
},
"output": {
"excentralAngleDegrees": 60
}
}Limitations and assumptions
- The result is the corresponding angle of the excentral triangle under the intended geometric construction, not the original triangle's exterior angle; no triangle or excenters are constructed or verified.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Construct the triangle from coordinates or solve the complete geometric constraints when consistency matters. Match side ordering, angle units, and internal-versus-external conventions to the intended identity.
References
Similar or alternative tools
- Geometry: Triangle Angle Bisector Foot
Validate three noncollinear two-dimensional vertices with A distinct from B and C.
- Triangle Exradius From Area Semiperimeter
Return area/(semiperimeter-oppositeSide).