| 释义 |
even function The real function f is an even function if f(−x) = f(x) for all x (in the domain of f). Thus the graph y = f(x) of an even function has the y‐axis as a line of symmetry. The following are even functions of x: 5, x2, x6−4x4 + 1, 1/(x2−3), cos x. Compare odd function.
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