The Cartesian coordinates of a point in the xy plane are (−1.2, −1.8). Find the polar coordinates of the point.

Question

r = ?

𝜃 = ? ° counterclockwise from the +x-axis

Answer 1

r = √(-1.2)² + (-1.8)² = 0.6√13 = 3√13/5;

tanθ = (-1.8/-1.2) = 1.5; θ = tan^-1(1.5) + π.

Polar coordinates: (3√13/5, tan^-11.5 + π)