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# What is -5^2? watch

1. this sounded like nooby trolling to me, it's 25 or -25 depending on symbols involved
2. (Original post by Good bloke)
You can agree what you like; this is not a matter of opinion. Look at the link I provided earlier.
It just seemed like the guy was trying to input something that wasn't really neccesary - it was quite obvious this was a troll.
3. (Original post by IBiot Ash '08)
this sounded like nooby trolling to me, it's 25 or -25 depending on symbols involved
He was quite clear about the symbols involved. It was -5^2. The answer is -25.
4. (Original post by Good bloke)
Oh dear! The unary operator has lower precedence than exponentiation, and operates on the result of 5^2.

If you don't believe me go here: http://mathforum.org/library/drmath/view/53194.html

The reason calculators get it wrong so often is that they use the minus key for two purposes and a zero is always on the display at the commencement of the operation.
So was I wrong or right XD

5. or

it's not that difficult to understand, this thread has gone on far too long
6. (Original post by neomilan)

or

it's not that difficult to understand, this thread has gone on far too long
You got the first one wrong, based on conventional unary operator precedence rules, so perhaps the thread still has legs. Or perhaps it is more difficult to understand than you think?
7. NEVER, and I say again, NEVER EVER STATE THAT YOUR PROOF IS SO BECAUSE THE CALCULATOR SAYS SO.

No 1. Calculators are lying, cheating, decieving, yet lovable little monsters.
No 2. You need some kind of formal watertight proof.

Thank you

 whoops. I quoted the wrong person [/edit]
8. BRACKETS
INDICES
DIVISION
MULTIPLICATION
SUBTRACTION

Is actually BI(DM)(AS).
9. (Original post by Good bloke)
You got the first one wrong, based on conventional unary operator precedence rules, so perhaps the thread still has legs. Or perhaps it is more difficult to understand than you think?
i'm going by regular maths and not advance thinking
10. ok i agreee -5^2 is equal to -25

but if you were asked what minus 5 squared is what would you reply with? 25 every time
11. (Original post by Glutamic Acid)
BRACKETS
INDICES
DIVISION
MULTIPLICATION
SUBTRACTION

Is actually BI(DM)(AS).
You mean BODMAS. lol (Here starts the BODMAS vs. BIDMAS debate. )
12. (Original post by Mathematician!)
You mean BODMAS. lol (Here starts the BODMAS vs. BIDMAS debate. )
"Indices" is infinitesimally more descriptive than "order".
13. (Original post by DeanK2)
FAIL
Well, no. Would you agree that x² - x² = 2x²?
14. -5^2 is -25

According to BIDMAS you square first, and then take account of the minus sign.

The answer is -25. Usually I take note of other people's opinions, but this is Mathematics. If you have a different opinion, you're wrong.
15. (Original post by im so academic)
-(5^2) = -25
(-5)^2 = 25

simple as.
But that wasn't the question, so don't spam.
16. (Original post by Good bloke)
No, it was written quite unambiguously, but only for those that understand the precedence rules for unary operators.
Well, it's generally a good idea to make things clear using parentheses so that the author's intention is easily understood, otherwise you are relying on both the author and reader correctly remembering the sometimes-inconsistent conventions regarding precedence. In this case, there is definitely ambiguity over what the author's intention is, so I think the other poster's point is a fair one.
17. (Original post by Glutamic Acid)
"Indices" is infinitesimally more descriptive than "order".
Yes, but BODMAS says the word "BOD" in it. Hehehe.
18. oh not this again.
19. (Original post by Kolya)
Well, it's generally a good idea to make things clear using parentheses so that the author's intention is easily understood, otherwise you are relying on both the author and reader correctly remembering the sometimes-inconsistent conventions regarding precedence. In this case, there is definitely ambiguity over what the author's intention is, so I think the other poster's point is a fair one.
If you properly understand the rules, and they are taught in all British schools, there is no ambiguity in the OP's question at all - there is no room for debate. We are talking about maths, for heaven's sake.
20. (Original post by kcfch)
oh not this again.
Exactly!

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Updated: November 10, 2008
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