1. The problem statement, all variables and given/known data Problem is regarding approximating the value of a in y= a cosh(x/a) using Newton's method, and then use a to find the length of the rope. That equation represents the curve formed by a rope hanging with it's ends attached to poles at a distance 2b. (cosh() = hyperbolic cosine) distance between poles = 2b = 400 ft. sag = S = 30 ft. 2. Relevant equations (previously proven eqns) L = 2 a sinh(b/a) where L is the length of the rope a is a physical constant and 2b is the distance between the poles that the rope is hanging from S = a cosh(b/a) - a where S is the sag (vertical distance between highest and lowest points on the rope) a is a physical constant 2b is distance between poles 3. The attempt at a solution I am really not sure how to do this, as I do not know how/why Newton's method could be used to get a value for a. Also, they gave a hint, a clip from the Calc book I am reading: "[Hint: First let u = 200/a]"