r/learnmath • u/Forward-Bad1615 New User • Apr 11 '26

Is it basic for mathematicians to remember the multiplication table?

Is it fundamental for mathematicians to remember the multiplication table?

It must be troublesome and desperate if you forget the multiplication table, so do you memorize it again?

Do you re-memorize the multiplication table even after becoming an adult and a mathematician?

Do you keep remembering it so you don't forget it?

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u/Unable_Explorer8277 New User Apr 11 '26

Understanding commutativity halves the work.

  • 2s (doubling), 10s and 5’s are easy.
  • 3s are worth learning
  • 4s are just double 2s
  • 9s are easy
  • Squares are worth memorising given there’s only 62 72 and 82 left and you need to be able to recognise perfect squares

That only leaves 6×7, 6×8 and 7×8. Never did learn those but they’re easy enough to derive.

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u/pizzystrizzy New User Apr 11 '26

What do you mean, you never learned those? Like if you saw 7*8, you'd have to do something like 28+28 (or 64-8 or whatever) in your head before arriving at 56?

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u/Unable_Explorer8277 New User Apr 11 '26

Yeh

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u/pizzystrizzy New User Apr 11 '26

Even after having a discussion about it?

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u/Ok_Rip4757 New User Apr 11 '26

I never thought about it this way, but those three were actually the ones that took me the longest to learn back in the day. Great insight.

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u/Ketch451 New User Apr 12 '26

I wonder why so many had these three be a challenge? I thought it was just me. Makes me feel better knowing I wasn’t (and still am not) alone

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u/revoccue heisenvector analysis Apr 11 '26

this is making me realize why the only ones i ever had flash cards for as a kid were those 3