MATHEMATICS · Multi-part · AP · AP Precalculus · Trigonometric and Polar Functions · Trigonometric and Polar Functions
Problem
For an angle θ in standard position, it is given that tanθ=43 and θ lies in Quadrant III.
(i) Find the exact values of sinθ and cosθ.
(ii) Write the coordinates of the point on the unit circle that corresponds to θ.
(iii) List all angles ϕ in the interval 0≤ϕ<2π having the same sine value as θ, and write the coordinates of their corresponding points on the unit circle.
(iv) Show algebraically that each of the points obtained in part (iii) satisfies the equation x2+y2=1. Explain the result.