Trigonometric value

Tan(150°) = -√3/3

Tangent — sine divided by cosine, equivalently opposite/adjacent in a right triangle; undefined where cos = 0.

How to derive tan(150°)

tan(150°)=33tan(150°) = -\dfrac{\sqrt{3}}{3}

150° is in quadrant II. Reference angle = 30°, tangent negative in Q2, so tan(150°) = −tan(30°) = −√3/3.

Unit-circle context

The angle 150° corresponds to 5π/6 radians and sits Quadrant II on the unit circle.

Its reference angle is 30°, which is why tan(150°) shares its absolute value with tan(30°).

Other trig values at 150°

Related tan values

Frequently asked

What is the exact value of tan(150°)?
The exact value is -√3/3. Its decimal approximation is -0.57735.
How do you derive tan(150°)?
150° is in quadrant II. Reference angle = 30°, tangent negative in Q2, so tan(150°) = −tan(30°) = −√3/3.
What is 150° in radians?
150° equals 5π/6 radians (multiply degrees by π/180).

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