(追記) (追記ここまで)
Root
A solution to an equation of the form f(x) = 0. Roots may be real or complex.
Note: The roots of f(x) = 0 are the same as the zeros of the function f(x). Sometimes in casual usage the words root and zero are used interchangeably.
Example:
The roots of x2 – x – 2 = 0 are x = 2 and x = –1.
The equation is satisfied if we substitute either x = 2 or x = –1 into the equation.