e Find tan a B f Find the quadrant containing the angle a 3 Problem 5 Verify each identity a secx tan x sec x b tan 4x csc 4x cot 4x sec 4x C d sin t 6 sint 9 3 csc t 1 sint 3 csc t sect 1 cos t sec x sec t e f g sin x 2 sin x 1 cos x COS sin 0 cos 0 cos a B cos a B h tan sec 0 cos 0 0 1 sin x 1 sin x 1 tan a tan 3 1 tan a tan 3 1 tan 0 1 tan 0 Problem 6 If a person with weight W bends at the waist with a straight back then the force F in pounds exerte on the lowe back muscles may be approximated by the function F 3 2 89W sin 8 The ang B is the angle between a person s torso ard the horizontal a Use the sum and difference identities to rewrite the function F B in terms of cosine b Suppose the person is standing straight measure the force ororted on their book