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(-27)^2/3
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nocturne slrpnk.net nocturne@slrpnk.net
Joined: 2025-06-13
Quote

This is the kind of shower thought I have. I am envious of those that have real shower thoughts

23   Original
printf("%s", name); piefed.blahaj.zone akunohana@piefed.blahaj.zone
Joined: 2026-03-30
#2 · Quote Reply

Sincere question: why do you put that negative -27 in parentheses?

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mschae discuss.mschae23.de mschae@discuss.mschae23.de
Joined: 2026-02-27
#3 · Quote Reply

Sincere question: why do you put that negative -27 in parentheses?

-27^2/3 would come out to a different number, because the exponentiation has a higher precedence than the negation

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bob_omb_battlefield sh.itjust.works bob_omb_battlefield@sh.itjust.works
Joined: 2023-07-08
#4 · Quote Reply

Sincere question: why do you put that negative -27 in parentheses?

Presumably to avoid ambiguity as to whether the thing to exponentiate is 27 or -27.

2
printf("%s", name); piefed.blahaj.zone akunohana@piefed.blahaj.zone
Joined: 2026-03-30
#5 · (edited) Quote Reply

-27^2/3 would come out to a different number, because the exponentiation has a higher precedence than the negation

Ah, so without parentheses, it would be:
x = -27^2
x / 3?
That doesn't sound very intuitive though...

5
mschae discuss.mschae23.de mschae@discuss.mschae23.de
Joined: 2026-02-27
#6 · (edited) Quote Reply

Ah, so without parentheses, it would be: x = -27^2 x / 3? That doesn't sound very intuitive though...

yup:

(-27)^2/3 = ((-27) ^ 2) / 3

-27^2/3 = (-(27 ^ 2)) / 3

The reason is that you almost always want the negation to happen after the exponentiation, because it otherwise wouldn't have any effect (at least when the exponent is even).

5
printf("%s", name); piefed.blahaj.zone akunohana@piefed.blahaj.zone
Joined: 2026-03-30
#7 · Quote Reply

yup: (-27)^2/3 = ((-27) ^ 2) / 3 -27^2/3 = (-(27 ^ 2)) / 3 The reason is that you almost always want the negation to happen after the exponentiation, because it otherwise wouldn't have any effect (at least when the exponent is even).

Thanks! 😃

3
AHemlocksLie lemmy.zip AHemlocksLie@lemmy.zip
Joined: 2024-03-10
#8 · (edited) Quote Reply

(-27)^2/3^

3^3^ = 27 => 3 = 27^1/3^ => -3 = (-27)^1/3^ => (-27)^2/3^ = ((-27)^1/3^)^2^ = (-3)^2^ = 9

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nocturne slrpnk.net nocturne@slrpnk.net
Joined: 2025-06-13
#9 · Quote Reply

Sincere question: why do you put that negative -27 in parentheses?

-27^2/3^ is a different answer and problem than (-27)^2/3^.

(-27)^2^ is (-27)(-27) while -27^2^ is (-27)(27).

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TranquilTurbulence lemmy.zip TranquilTurbulence@lemmy.zip
Joined: 2024-05-19
#10 · (edited) Quote Reply

-27^2/3^ is a different answer and problem than (-27)^2/3^. (-27)^2^ is (-27)(-27) while -27^2^ is (-27)(27).

I like to think of -27^2 as -(27^2).

3
TranquilTurbulence lemmy.zip TranquilTurbulence@lemmy.zip
Joined: 2024-05-19
#11 · Quote Reply

You're having some complex thoughts.

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wholookshere lemmy.blahaj.zone wholookshere@lemmy.blahaj.zone
Joined: 2024-06-13
#12 · Quote Reply

I like to think of -27^2 as -(27^2).

That's the common shorthand yes, but its still treated like its there.

The other interpretation is just as valid though.

3
TrippinMallard lemmy.ml TrippinMallard@lemmy.ml
Joined: 2026-02-18
#13 · (edited) Quote Reply

=(-1)^(2/3) * (3^3)^(2/3) 

= e^(2*i*pi/3) * 9 

= (cos(2pi/3) + i * sin(2pi/3)) * 9

= (-1/2 + i * sqrt(3)/2) * 9
2
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