How do you evaluate sine, cosine, tangent of −405∘ without using a calculator? Trigonometry Right Triangles Trigonometric Functions of Any Angle 1 Answer sankarankalyanam Feb 20, 2018 sin(−405)=−(1√2) cos(−405)=(1√2) tan(−405)=−1 Explanation: sin(−405)=sin(−360−45)=sin(−45)=−sin45=−(1√2) cos(−405)=cos(−360−45)=cos(−45)=cos45=(1√2) tan(−405)=tan(−360−45)=tan(−45)=−tan45=−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∘? How do you find the value of cot300∘? 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−tan135? How do you know if sin30=sin150? How do you show that (cosθ)(secθ)=1 if θ=π4? See all questions in Trigonometric Functions of Any Angle Impact of this question 4872 views around the world You can reuse this answer Creative Commons License