Math Is Fun Forum

Al-Allo

Member

Registered: 2012-08-23

Posts: 324

Quick question

Here's an easy thing :

I did the error of doing this :

Which is clearly false.

I know what is the correct way of doing it, because the real answer is positive one.

But just to know, I should have done BEMDAS to have avoided that incorrect way of doing ? Right ? (It concerned the priority of operations?Just want to be sure I've learned correctly from my error)

Thank you !

Last edited by Al-Allo (2013-07-04 09:29:36)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Quick question

Hi;

PEMDAS. Parentheses first over exponentiation. In the wrong answer you brought the 14 inside the parentheses. You gave it higher priority, that is the reason for the error.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Al-Allo

Member

Registered: 2012-08-23

Posts: 324

Re: Quick question

Ah! Ok, exactly what I thought. I just wanted to hear it from someone else, to assure myself I learned from my error. THank you again Bobbym !

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Quick question

To check your work you can use a calculator or google's calculator. They never make a mistake with the order of operations. If you do not get their answer you know you did not follow the order of operations correctly.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Al-Allo

Member

Registered: 2012-08-23

Posts: 324

Re: Quick question

To check your work you can use a calculator or google's calculator. They never make a mistake with the order of operations. If you do not get their answer you know you did not follow the order of operations correctly.

That's what I did, but I wanted a human approbation also ^^ Thank you again ! SOmetimes, I need to have more confidence in what I do. ( I hate when I lack it)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Quick question

Confidence comes from doing something and getting good results. When you get bad results or mixed results your confidence will waver. Doubt will set in.

You conquer doubt with practice. Practice of doing it the right way. It takes a unique amount for each person.

but I wanted a human approbation

Here, I would trust any calculator over 10 bobbym's any day of the week and twice on Sunday. Look at what it did:

Now anyone could do it by just following the rule that parentheses and nested ones go first! Wunderbar!

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.