Definition of tangent plane:
(n) :
given a point P on a surface M, the tangent plane of M at point P, denoted by TP(M), is the plane passing through P which contains the tangent lines of all the curves on M passing through P
Definition of tangent plane:
(n) :
given a point P on a surface M, the tangent plane of M at point P, denoted by TP(M), is the plane passing through P which contains the tangent lines of all the curves on M passing through P