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Maths Help (-x squared)

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Reply 21
Like others have said, depends how it is interpreted.

We could have: (x2) -(x^{2}) or (x)2 (-x)^{2} .

For x2 -x^{2} , then using the rule, it is (x2) -(x^{2}) .

Giving another demostration
Let:

f(x)=x3x2=x2+x3=x2(x1). \displaystyle f(x) = x^{3} - x^{2} = -x^{2} + x^{3} = x^{2} (x - 1).

Hopefully, we all agree that:

f(2)=2322=22+23=22(21), \displaystyle f(2) = 2^{3} - 2^{2} = -2^{2} + 2^{3} = 2^{2} (2-1),

=84=4, \displaystyle = 8 - 4 = 4, while: f(2)=23228+4. \displaystyle f(2) = 2^{3} - 2^{2} \neq 8 + 4.
(edited 7 years ago)
Reply 22
When people can't BODMAS/BIDMAS :rofl:
Original post by simon0
Like others have said, depends how it is interpreted.

We could have: (x2) -(x^{2}) or (x2) (-x^{2}) .

...
Original post by 1 8 13 20 42
When people can't BODMAS/BIDMAS :rofl:


Like I said before to another person, THAT IS NOT THE ISSUE! The issue is knowing where the brackets are in the first place! Surely that's more important to sort out than going for BODMAS straight away...
Reply 25
Original post by ValerieKR
...


I do apologise, now corrected.

It pays not to rush...
Reply 26
Original post by Uni12345678
Like I said before to another person, THAT IS NOT THE ISSUE! The issue is knowing where the brackets are in the first place! Surely that's more important to sort out than going for BODMAS straight away...


Well, I assume that what is written is what is there, and that if there were brackets, OP would have included them.
Original post by 1 8 13 20 42
Well, I assume that what is written is what is there, and that if there were brackets, OP would have included them.


Yes but how can you solve this using BODMAS or BIDMAS if there aren't any brackets given at the start? I get that the OP does not have brackets in the question and we are trying to figure out the form of brackets this notation is intending.
Reply 28
Original post by Uni12345678
Yes but how can you solve this using BODMAS or BIDMAS if there aren't any brackets given at the start? I get that the OP does not have brackets in the question and we are trying to figure out the form of brackets this notation is intending.


Simple. If there aren't brackets, you first go to the indices. Plenty of mathematical expressions don't have brackets but we don't care.
edit: I recognise that the OP may have made a mistake by neglecting to include brackets from the original question. But I hope and expect that they haven't, and the question merely said " -x^2 "
(edited 7 years ago)
Original post by 1 8 13 20 42
Simple. If there aren't brackets, you first go to the indices. Plenty of mathematical expressions don't have brackets but we don't care.


Okay I get what you're saying...
The answer is -4 as the -1 is not squared.

-2^2 is the same as -(2)^2=-4

It's not +4, that would be like saying ab^2 = a^2 x b^2 ; the minus 1 is not squared.

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