Tan 77 Degrees

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

What is tan 77°?

Answer

tan 77° ≈
4.3315

Angle in radians: 77° = 77π/180. The point of the angle is in quadrant I, where tangent is positive.

≈ — rounded to 4 decimal places. tan 77° can't be written with square roots: 77° is not a multiple of 3°.

tan 77° = sin 77° / cos 77° ≈ 4.3315

xyOP

P(cos 77°, sin 77°) ≈ (0.2250, 0.9744)

T(1, tan 77°) ≈ (1, 4.3315) — where line OP meets the line x = 1; T is beyond the drawing, the arrow points to it.

All four functions of 77°
FunctionExact valueDecimal
sin 77°—≈ 0.9744
cos 77°—≈ 0.2250
tan 77°—≈ 4.3315
cot 77°—≈ 0.2309

See Also

FAQ

What is tan 77°?

tan 77° ≈ 4.3315

Why does tan 77° have no exact value?

A trigonometric value of a whole number of degrees can be written with square roots only when the angle is a multiple of 3°. 77° is not, so no such exact form exists; the value is used as a decimal: tan 77° ≈ 4.3315.

Why does a calculator show −32.2686 for tan 77?

The calculator is in radian mode (RAD): it takes tan 77 as the tangent of 77 radians, tan 77 rad ≈ −32.2686. Switch it to degrees (DEG): tan 77° ≈ 4.3315. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.