Is it true that $\mathbb{E}|X-\mathbb{E}(X)|=0$ where $\mathbb{E}(X) $ is finite?

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I'm not sure

  1. whether this is always true? and
  2. If it is true, whether it is a trivial assertion to make?

I've tried integrating using the definition of expectation, but I'm not getting anywhere with it.

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It is true if and only if $X$ is a constant random variable. Reason: $|X-\mathbb E X|$ is non-negative random variable and its expectation can be $0$ only when it is zero almost surely.