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Comment on Ask HN: What is -2^2?parent

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HP48 is RPN, which sidesteps precedence issues. So, here you explicitly need to decide if you want 2 NEG 2 ^ (i.e. (-2)^2) or 2 2 ^ NEG (i.e. -(2^2)).

The traditional order of operations is what the TI series does. In essence, it assumes you want the second form.

By the way, on my HP50G in algebraic mode, typing '-2^2' does give -4.

I apologize. You are correct, the HP48gx is RPN only. Don't know why I thought otherwise. I had it in my head for some reason that 48 did both (it kind of does but not really) and that it gave the answer as 4.

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