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## Main Question or Discussion Point

I'm trying to work through a derivation and am getting some funny results. For example, when trying to compare some expressions, Mathematica was telling me they weren't equal, and when I worked them out by hand, I new they were equal. I then tried something like this:

ExpandAll[x] === ExpandAll[x]

x === ExpandAll[x]

Returns

True

False

The second shows me that the form an expression determines If mathematica can perform some computations. But how do I ever trust this?? Now I'm tyring to compare two vectors, that I'm almost positive are the same, but mathematica returns: False. My trick of ExpandAll doesn't work in this case either.

can someone explain why this occurs, or how to reliably compare two expressions of different forms?

Thanks

ExpandAll[x] === ExpandAll[x]

x === ExpandAll[x]

Returns

True

False

The second shows me that the form an expression determines If mathematica can perform some computations. But how do I ever trust this?? Now I'm tyring to compare two vectors, that I'm almost positive are the same, but mathematica returns: False. My trick of ExpandAll doesn't work in this case either.

can someone explain why this occurs, or how to reliably compare two expressions of different forms?

Thanks