cos9 - Wolfram|Alpha

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Input

cos(9°)

Decimal approximation

0.98768834059513772619004024769343726075840686158988043492390480163807293596...

Alternate form

sqrt(5 - sqrt(5))/4 + (1 + sqrt(5))/(4 sqrt(2))

Number line

Number line

Continued fraction

[0; 1, 80, 4, 2, 7, 3, 1, 1, 42, 1, 12, 18, 16, 1, 1, 2, 2, 7, 4, 1, 1, 9, 10, 1, 8, 2, 4, 4, ...]

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