He relationship between rectangular and rotational coordinates can be represented by the vector equation: r = xi +yj = rcos(theta)i+rsin(theta)j What values in radians makes x minimum y maximum and x = -y Ans : x minimum = -r when theta = 180 degrees + any multiple of 360 degrees y minimum = -r when theta = 270 degrees + any multiple of 360 degrees x = -y when theta = 135 degrees + any multiple of 180 degrees.