1 also called zymogenic cell. Any one of the columnar epithelial cells or the cuboidal epithelial cells that line the gastric glands and secrete pepsinogen and intrinsic factor, which are needed for the digestion and absorption of vitamin B 12 and the normal development of red blood cells.
The red and blue vectors are the elements of the basis; the green vector can be given with the basis vectors. In linear algebra, a basis is a set of vectors in a given vector space with certain properties: 1  One can get any vector in the vector space by multiplying each of the basis vectors by different numbers, and then adding them up.  If any vector is removed from the basis, the property above is no longer satisfied.
An orthogonal matrix Q is necessarily invertible (with inverse Qâ1 = QT), unitary (Qâ1 = Qâ) and therefore normal (QâQ = QQâ) in the reals. The determinant of any orthogonal matrix is either +1 or â1. As a linear transformation, an orthogonal matrix preserves the dot product of vectors, and therefore acts as an isometry of Euclidean space, such as a rotation or reflection. In other words, it is a unitary transformation. The set of n Ã n orthogonal matrices forms a group O(n), known as the orthogonal group. The subgroup SO(n) consisting of orthogonal matrices with determinant +1 is called the special orthogonal group, and each of its elements is a special orthogonal matrix.