Trigonometry Values Pi/10
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|  | (1) |
So we have
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|  | (2) |
and
 | (3) |
| |  | (4) |
| |  | (5) |
 | |  | (6) |
 | |  | (7) |
 | |  | (8) |
 | |  | (9) |
An interesting near-identity is given by
 | (10) |
.See also Decagon, Decagram- Signpost
- Signum
- Silver Constant
- Silverman Constant
- Silverman's Sequence
- Silver Mean
- Silver Ratio
- Similar
- Similarity Axis
- Similarity Dimension
- Similarity Point
- Similarity Transformation
- Similitude Center
- Similitude Ratio
- Simple Algebra
- Simple Continued Fraction
- Simple Curve
- Simple Graph
- Simple Group
- Simple Harmonic Motion
- Simple Harmonic Motion Quadratic Perturbation
- Simple Harmonic Oscillator
- Simple Interest
- Simple Polygon
- Simple Ring