| Cos (0θ) = 1 | T0 (x) = 1 | |
| Cos (1θ) = cos θ | T1 (x) = x | |
| Cos (2θ) = 2 cos2 θ − 1 | → | T2 (x) = 2x2 − 1 |
| Cos (3θ) = 4 cos3 θ − 3 cos θ | T3 (x) = 4x3 − 3x | |
| Cos (4θ) = 8 cos4 θ − 8 cos2 θ + 1 | T4 (x) = 8x4 − 8x2 + 1 |
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