What happens when you try? Are you getting a box with an "x" in it, or is the code showing up instead of the picture?
Post an example here... first post an image here the way you are trying it, and then post the line of markup code following it, but add spaces before and after the "[" and "]" so we can read the code you are typing into the post.
We can troubleshoot this.
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-- The world is what we make of it --
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