When a pilot banks an aircraft moving at a speed v, in metres per second, at an angle , the radius of the turn that results is given by the formula r = v^2/g tan (22/7/2 - ) where g is the acceleration due to gravity, or 9.8 m/s2 . use an appropriate equivalent trigonometric expression to prove that this formula can be simplified to r = v^2/g tan what is the appropriate equivalent trigonometric expression