4. Determine where f(x) = aresin (12 -2x) is increasing. d -1 5. Prove (arecot(:)) = Be sure to provide a written justification for your work. 1+ 2 6. An airplane, flying at 450 km/hr at a constant altitude of 5 km, is approaching a camera mounted on the ground. Let A be the angle of elevation above the ground at which the camera is pointed. When A = #/3, how fast does the camera have to rotate in order to keep the plane in view