How to Solve Any Triangle: First, Forget the Law of Sines and the Law of Cosines
Computer algebra systems (CASs) have made, and will continue to make, changes in what is taught in mathematics courses at all levels. Just as scientific calculators made teaching computations with logarithms obsolete, CASs will render obsolete many other topics in the curriculum. Some will be formulas and procedures for computations that are no longer necessary to solve the problems for which they were originally developed. The mathematical problems will remain; we will just use more efficient ways to solve them. A good example is Newton's method for approximating the zeros of an expression. Using Newton's method to find roots by hand has been rendered obsolete by graphing calculators that can either find the roots exactly or do the approximations faster and more accurately.