Let f (x) be an odd function defined on R. when x < 0, f (x) = x23, then f (8)=______ .

Let f (x) be an odd function defined on R. when x < 0, f (x) = x23, then f (8)=______ .

Because f (x) is an odd function, f (- 8) = - f (8) = - 823 = - 4