How do you find the value of #tan (-135) #? Trigonometry Right Triangles Trigonometric Functions of Any Angle 1 Answer Rafael Oct 17, 2015 #tan(225°)=1# Explanation: #-135°# is coterminal with #225°# #tan(-135°)=tan(225°)# #225°# is a special angle. #tan(225°)=1# 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 6697 views around the world You can reuse this answer Creative Commons License