What is cot 75 degrees? Trigonometry Right Triangles Trigonometric Functions of Any Angle 1 Answer Nghi N. Jun 6, 2015 Use the trig identity: #tan (a + b) = (tan a+ tan b)/(1 - tan a.tan b)# #tan 30 = sqrt3/3 #; tan 45 = 1 #tan 75 = tan (30 + 45) = (3 + sqrt3)/3.(3)/(3 - sqrt3) = (3 + sqrt3)/(3 - sqrt3)# Answer link Related questions How do you find the trigonometric functions of any angle? What is the reference angle? How do you use the ordered pairs on a unit circle to evaluate a trigonometric function of any angle? What is the reference angle for #140^\circ#? How do you find the value of #cot 300^@#? What is the value of #sin -45^@#? How do you find the trigonometric functions of values that are greater than #360^@#? How do you use the reference angles to find #sin210cos330-tan 135#? How do you know if #sin 30 = sin 150#? How do you show that #(costheta)(sectheta) = 1# if #theta=pi/4#? See all questions in Trigonometric Functions of Any Angle Impact of this question 24254 views around the world You can reuse this answer Creative Commons License