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# Subbing in a value for -x squared.. do I add brackets around x? watch

1. So I wanted to sub in a value for x into:

In this case the value I want to sub in is 4.

So would I do: which gives -16, or

would I do: which gives 16?

I have a feeling that it will be -16, as -x is same as -1(x)? Is this right? Is there a better reason?

Thanks so much
2. (Original post by Lid-the-squid)
So I wanted to sub in a value for x into:

In this case the value I want to sub in is 4.

So would I do: which gives -16, or

would I do: which gives 16?

I have a feeling that it will be -16, as -x is same as -1(x)? Is this right? Is there a better reason?

Thanks so much
Brackets, Indices, Division, Multiplication, Addition, Subtraction.
THe Indices occur before the subtraction -x^2
= -(4)^2=-16
3. It would be -(x)^2 so -(4)^2 = -16
4. (Original post by Lid-the-squid)
So I wanted to sub in a value for x into:

In this case the value I want to sub in is 4.

So would I do: which gives -16, or

would I do: which gives 16?

I have a feeling that it will be -16, as -x is same as -1(x)? Is this right? Is there a better reason?

Thanks so much
This is no different to 3x^2 where you would want 3(x^2) not (3x)^2

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Updated: March 6, 2013
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