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Glitch in the matrix (ani.social)

submitted 11 months ago by [email protected] to c/[email protected]

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[–] [email protected] 6 points 11 months ago (2 children)

The comment from subignition explains that the phone's answer, 16, is what you get by strictly following PEMDAS: the rule is that multiplication and division have the same precedence, and you evaluate them from left-to-right.

The calculator uses a different convention where either multiplication has higher priority than division, or where "implicit" multiplication has higher priority (where there is no multiply sign between adjacent expressions).

[–] [email protected] 2 points 11 months ago (1 children)

But explicit multiplication is part of the parenthesis, so still comes before division or exponent

[–] [email protected] 3 points 11 months ago (1 children)

The parentheses step only covers expressions inside parentheses. That's 2 + 2 in this case. The times-2 part is outside the parentheses so it's evaluated in a different step.

[–] [email protected] 1 points 8 months ago

The parentheses step only covers expressions inside parentheses

No, it doesn't

[–] [email protected] 1 points 8 months ago

16, is what you get by strictly following PEMDAS

except 1 is what you get from strictly following PEMDAS. If you got 16 then you missed one of more rules.

the rule is that multiplication and division have the same precedence, and you evaluate them from left-to-right

Go back and read your link again. You'll find they're obeying The Distributive Law. i.e. solve all brackets first, from inner-most out.

“implicit” multiplication

There's no such thing as implicit multiplication