Square and Compasses any Masonic symbol) that is used by Freemasonry as a whole. In many English speaking countries, the Square and Compasses are depicted with the letter "G" in the center. The letter has multiple meanings, representing different words depending on the context in which it is discussed. The most common is that the "G" stands for Geometry, and is to remind Masons that Geometry and Freemasonry are synonymous terms described as being the "noblest of sciences", and "the basis upon which the superstructure of Freemasonry, and everything in existence in the entire universe is erected. In this context it can also
Square root of a matrix a "positive-semidefinite matrix" has precisely one positive-semidefinite square root, which can be called its "principal square root". While the square root of a nonnegative integer is either again an integer or an irrational number, in contrast an "integer matrix" can have a square root whose entries are rational, yet not integer. For example, the matrix formula_8 has the non-integer square root formula_9 as well as the integer square root matrix formula_10. The 2×2 identity matrix is another example. A 2×2 matrix with two distinct nonzero eigenvalues has four square roots. More generally, an matrix with "distinct nonzero eigenvalues" has 2