# How to turn sin, cos, and tan into radicals.For example, how to turn tan30 into a radical.

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You need to know that sin, cos and tan are trigonometric functions and some of the values of these functions are expressed using irrational numbers.

Take several values between 0 and 90 degrees.

Take the angle of 30 degrees:

`sin 30 = 1/2 ; cos 30 = sqrt3/2 and tan 30 = sin 30/ cos 30 = sqrt3/3`

Take the angle of 45 degrees:

`sin45 = sqrt 2/2 ; cos45 = sqrt2/2 and tan45 = sin 45/ cos45 = 1`

Take the angle of 60 degrees:

`sin 60 = sqrt3/2 ; cos 60 = 1/2 and tan 30 = sin 60/ cos 60 = sqrt3`

**Therefore, in some of the values of the functions sine, cosine and tangent you may find irrational numbers (radicals).**