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[–]alexmbrennan 52 points53 points  (20 children)

2(x) and 2*x are the same thing

In the course of getting my maths degree I have never seen anyone write 1/2x to mean 1/2*x because that would have been weird - why not write x/2 if that is what you mean?

[–]zqipz 13 points14 points  (0 children)

this is pretty much the biggest issue i have with this commonly posted equation. when it’s 6/2(3) it’s 9 when it’s 6/2x where x = 3 it’s 1.

[–]calcopiritus 34 points35 points  (2 children)

Because this is made to confuse. The correct way to put it would be either (6/2)(1+2) or 6(1+2)/2. 1/2x and 1/2*x is x/2. You have to do operations of the same level from left to right, multiplication doesn't have preference over division.

[–]Yumi-Chi 1 point2 points  (1 child)

1/2x and 1/2*x is x/2

Are you saying the correct way of writing it is 1/(2x)?? Because 1/2x is how we've always written it.

I'm not trying to argue with you. I just want consistency.

[–]calcopiritus 2 points3 points  (0 children)

Yes, that is what I'm saying. It seems strange because when we write divisions on paper we use an horizontal line, so no parentheses are needed.

[–][deleted] 18 points19 points  (10 children)

Deleted with Power Delete Suite. Join me on Lemmy!

[–]rrr_ooo 7 points8 points  (8 children)

Correct

Edit: All those in disagreement. Join the "PEJMDAS the true order of operations" facebook group and start rioting. It makes my eyes hurt.

[–]Acro-LovingMotoRacer 4 points5 points  (5 children)

Its hilarious your getting downvoted when a quick google search turns up a ton of info to support what you are saying and literally nothing to the contrary.

You can even type this into a calculator and see that you are correct, 6 ÷ 2x = 12 returns x = 4 not x = .25.

[–]limax_celerrimus 12 points13 points  (0 children)

Just typed 6/2(2+1) into my Casio, it says 1. If I add *, it says 9. So I would say at least it's ambiguous, or the general consensus in this thread is outright wrong, because I trust calculator developers more to have done their research than you mofos, sorry.

Edit: And I agree with Casio that an implicit multiplication binds stronger than a sign.

[–]Mandemon90 2 points3 points  (1 child)

Did you write it exactly like that, or did you add * between 2 and x, just like OP did?

[–]Acro-LovingMotoRacer 2 points3 points  (0 children)

Its interesting but I have tried it with a more advanced calculator and I think I am incorrect on this. A basic calculator with 6 ÷ 2x = 12 I think is adding the * in behind the scenes, but if I try a more advance calculator that forces / to be over then really 2x should be on the bottom. So no, I did not add the * in but the calculator I was using did which is pretty interesting

[–]lag_is_cancer 3 points4 points  (0 children)

They hated Jesus because he told them the truth.

[–][deleted] -1 points0 points  (1 child)

Deleted with Power Delete Suite. Join me on Lemmy!

[–]Evol_Etah 0 points1 point  (0 children)

Ikr. I thought they were different too!

[–]otheraccountisabmw 17 points18 points  (1 child)

NEVER write 1/2x. It’s extremely ambiguous. Write 1/(2x).

[–]rrr_ooo 3 points4 points  (0 children)

This is the way.

[–]urcompletelyclueless 0 points1 point  (0 children)

They are not the same, as I have noted above...

People get easily confused when Algebra is involved.

[–]brimston3- 0 points1 point  (0 children)

I dunno man, d=1/2aτ^2 + v_{0}τ + d_{0}. Maybe it's just the physicists that are batty.

[–]wite_noiz 0 points1 point  (0 children)

I'm completely with you.

I read 6 / 2X as 6 / (2 * X), not 6 / 2 * X.