You are Here: Home >< Maths

# Maths Help (-x squared)

Announcements Posted on
Would YOU be put off a uni with a high crime rate? First 50 to have their say get a £5 Amazon voucher! 27-10-2016
1. If you have -x^2 and you subsitute in 2, does this become +4 or -4?

Thanks
2. Because a negative multiplied by another negative give you a positive the answer is +4.

Posted from TSR Mobile
3. (Original post by TomHibbs12)
If you have -x^2 and you subsitute in 2, does this become +4 or -4?

Thanks
Brackets
Indicies
Divison
Multiplication
Subtraction
4. (Original post by Hollybollybee109)
Because a negative multiplied by another negative give you a positive the answer is +4.

Posted from TSR Mobile
The negative comes after the squaring, so it is -(2^2) = -(2*2)=-4
5. Okay it depends whether you mean (-x)^2 or -(x)^2. If you mean the first one, where the negative sign is in the brackets, you are doing -x times -x, and two negatives make a positive so the answer will be 4. If it's the second one, then you are doing -(x times x) so the answer is -(2 x 2)= -4.

Posted from TSR Mobile
7. (Original post by Hollybollybee109)

Posted from TSR Mobile
8. Glad to see everyone's in agreement. Thanks for the answers - the question works if the answer is -4, but I was confused because I thought it would be +4. It has no brackets, simply -x^2
9. My thinking was it is essentially -1x^2, so x^2 multiplied by -1 would give you the answer
10. Like for example -3 x -10 = +30
-2^2 is the same as -2 x -2 = +4

Posted from TSR Mobile
11. (Original post by TomHibbs12)
My thinking was it is essentially -1x^2, so x^2 multiplied by -1 would give you the answer
Yeah personally this is what I think so I think it should be -4
12. (Original post by Hollybollybee109)
Like for example -3 x -10 = +30
-2^2 is the same as -2 x -2 = +4

Posted from TSR Mobile
is the same as not .
13. The back of the textbook can be wrong it has been many times before

Posted from TSR Mobile
14. It is basic intergers

Posted from TSR Mobile
15. (Original post by Hollybollybee109)
The back of the textbook can be wrong it has been many times before

Posted from TSR Mobile
I agree with Valerie. The answer is -4.
BIDMAS tells us that we work with indices before subtraction, so we must square the 2 first before dealing with the negative part.

-2² = -4

This is different to saying (-2)², in which case the answer would indeed be 4 as -2 x -2 = 4.
16. (Original post by Hollybollybee109)

Posted from TSR Mobile
We get that, we are trying to settle whether the question wants us to multiply two negatives or multiply two positives and then make it negative...
17. (Original post by Hollybollybee109)
It is basic intergers

Posted from TSR Mobile
Seems like you're having trouble understanding basic integers then.
18. (Original post by ValerieKR)
I disagree.
By induction, it is clearly +-4

Posted from TSR Mobile
19. (Original post by Hollybollybee109)
Like for example -3 x -10 = +30
-2^2 is the same as -2 x -2 = +4

Posted from TSR Mobile
I agree

Posted from TSR Mobile

## Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: September 13, 2016
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

Find out here

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read here first

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams