Possible Duplicate:
Differentiability of Norms
How would you find at which point the $L_p$ norm, $$|x|_p = (|x_1|^p + \dots + |x_n|^p)^{\frac{1}{p}}$$ is differentiable?
Possible Duplicate:
Differentiability of Norms
How would you find at which point the $L_p$ norm, $$|x|_p = (|x_1|^p + \dots + |x_n|^p)^{\frac{1}{p}}$$ is differentiable?