Feedback form
Hi! What do you think?

Drag it here or paste with Ctrl+V


    You can also email us on infocalculat.io

    Tan 690 Degrees

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

    What is tan 690°?

    Answer

    tan 690° =
    −√3/3 ≈ −0.5774

    Angle in radians: 690° = 23π/6. 690° = 360° + 330° — a full turn plus 330°, quadrant IV, where tangent is negative.

    ≈ — rounded to 4 decimal places.

    tan 690° = tan(690° − 360°) = tan 330°

    tan 330° = tan(360° − 30°) = −tan 30° = −√3/3

    tan 690° = sin 690° / cos 690° = (−1/2) / (√3/2) = −√3/3

    Half of an equilateral triangle with side 1: the hypotenuse is 1 and the leg opposite 30° is 1/2.

    tan 30° = (1/2) / (√3/2) = 1/√3 = √3/3

    xyOP

    P(cos 690°, sin 690°) ≈ (0.8660, −0.5)

    T(1, tan 690°) ≈ (1, −0.5774) — where line OP meets the line x = 1.

    +1 turn: the drawing shows 330°.

    All four functions of 690°
    FunctionExact valueDecimal
    sin 690°−1/2−0.5
    cos 690°√3/2≈ 0.8660
    tan 690°−√3/3≈ −0.5774
    cot 690°−√3≈ −1.7321

    Reference angle: tan 30° = √3/3

    See Also

    Share This Calculation
    Print
    https://calculat.io/en/number/trigonometry/tan--690Copy
    <a href="https://calculat.io/en/number/trigonometry/tan--690">Tan 690 Degrees: Tangent of 690° on the Unit Circle</a>Copy
    Facebook
    Twitter
    Telegram
    WhatsApp
    Viber
    Email
    Tan 690 Degrees: Tangent of 690° on the Unit Circle. tan 690° = −√3/3 ≈ −0.5774. The tangent is the ratio y/x of the point at 690° on the unit circle; 690° reduces to 30°.
    https://calculat.io/en/number/trigonometry/tan--690/generated.jpgCopy

    Tangent of nearby angles

    FAQ

    What is tan 690°?

    tan 690° = −√3/3 ≈ −0.5774

    How to remember sin 30°, sin 45° and sin 60°?

    Write them as √1/2, √2/2, √3/2: sin 30° = 1/2, sin 45° = √2/2, sin 60° = √3/2. Cosines are the same numbers in reverse order: cos 30° = √3/2, cos 45° = √2/2, cos 60° = 1/2; tan = sin / cos and cot = cos / sin. Here: tan 690° = −√3/3 ≈ −0.5774.

    Why does a calculator show −2.2368 for tan 690?

    The calculator is in radian mode (RAD): it takes tan 690 as the tangent of 690 radians, tan 690 rad ≈ −2.2368. Switch it to degrees (DEG): tan 690° = −√3/3 ≈ −0.5774. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.