What exactly is to define a function?
NOw the answer to this is supposed to be Arccos(-4/3) because
Is Cos(x) between -1 and +1 because it is DEFINED that way?
What about arcsec(3Pi)? Is that defined? Isn't arcsec 3Pi = 1/(arccos 3Pi)? and again isn't 3Pi greater than 1 thereby rendering it undefined because