what does ez mean in math

f, left parenthesis, x, right parenthesis, equals, x, plus, 2, left parenthesis, 1, comma, 3, right parenthesis, left parenthesis, 5, comma, 7, right parenthesis, f, left parenthesis, 3, right parenthesis, limit, start subscript, x, \to, 6, end subscript, f, left parenthesis, x, right parenthesis, limit, start subscript, x, squared, \to, 5, end subscript, limit, start subscript, x, \to, 5, end subscript, x, squared, limit, start subscript, x, \to, 25, end subscript, x, f, left parenthesis, x, right parenthesis, start color gray, start underbrace, start color black, 2, point, 999, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 3, end subscript, end color gray, start color gray, start underbrace, start color black, 4, point, 999, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 5, end subscript, end color gray, start color gray, start underbrace, start color black, 3, point, 001, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 3, end subscript, end color gray, start color gray, start underbrace, start color black, 5, point, 001, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 5, end subscript, end color gray, f, left parenthesis, 2, point, 999, right parenthesis, equals, 4, point, 999, f, left parenthesis, 3, point, 001, right parenthesis, equals, 5, point, 001, f, left parenthesis, 3, point, 00001, right parenthesis, equals, 5, point, 00001, limit, start subscript, x, \to, 3, end subscript, f, left parenthesis, x, right parenthesis, equals, 5, g, left parenthesis, x, right parenthesis, limit, start subscript, x, \to, minus, 7, end subscript, g, left parenthesis, x, right parenthesis, limit, start subscript, x, \to, 2, end subscript, x, squared, start color gray, start underbrace, start color black, 1, point, 999, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 2, end subscript, end color gray, start color gray, start underbrace, start color black, 3, point, 996001, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 4, end subscript, end color gray, start color gray, start underbrace, start color black, 2, point, 001, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 2, end subscript, end color gray, start color gray, start underbrace, start color black, 4, point, 004001, end color black, end underbrace, start subscript, start text, c, l, o, s, e, space, t, o, space, end text, 4, end subscript, end color gray, 2, point, 001, squared, equals, 4, point, 004001, 2, point, 0001, squared, equals, 4, point, 00040001, limit, start subscript, x, \to, 2, end subscript, x, squared, equals, 4, limit, start subscript, x, \to, 3, end subscript, f, left parenthesis, x, right parenthesis, limit, start subscript, x, \to, 3, end subscript, g, left parenthesis, x, right parenthesis, limit, start subscript, x, \to, 5, end subscript, g, left parenthesis, x, right parenthesis, limit, start subscript, x, \to, 6, end subscript, g, left parenthesis, x, right parenthesis, limit, start subscript, x, \to, 7, end subscript, g, left parenthesis, x, right parenthesis.