Cot 9 Degrees

Sin, Cos, Tan, Cot of an Angle
Function
Angle (°)

What is cot 9°?

Answer

cot 9° ≈
6.3138

Angle in radians: 9° = π/20. The point of the angle is in quadrant I, where cotangent is positive.

≈ — rounded to 4 decimal places. An exact form of cot 9° in square roots exists, but it is unwieldy — nested radicals.

cot 9° = cos 9° / sin 9° ≈ 6.3138

xyOP

P(cos 9°, sin 9°) ≈ (0.9877, 0.1564)

C(cot 9°, 1) ≈ (6.3138, 1) — where line OP meets the line y = 1; C is beyond the drawing, the arrow points to it.

All four functions of 9°
FunctionExact valueDecimal
sin 9°—≈ 0.1564
cos 9°—≈ 0.9877
tan 9°—≈ 0.1584
cot 9°—≈ 6.3138

See Also

Recalculate with different values ↑

Cotangent of nearby angles

Anglecot
6°≈ 9.5144
7°≈ 8.1443
8°≈ 7.1154
9°≈ 6.3138
10°≈ 5.6713
11°≈ 5.1446
12°≈ 4.7046

FAQ

What is cot 9°?

cot 9° ≈ 6.3138

Is there an exact value of cot 9°?

Yes: 9° is a multiple of 3°, and the values of such angles can be written with square roots — but the expression is unwieldy, with nested radicals built from the values of 18° and 15° (3° = 18° − 15°). In practice the decimal is used: cot 9° ≈ 6.3138.

Why does a calculator show −2.2108 for cot 9?

The calculator is in radian mode (RAD): it takes cot 9 as the cotangent of 9 radians, cot 9 rad ≈ −2.2108. Switch it to degrees (DEG): cot 9° ≈ 6.3138. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.

See Also