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

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    So I wanted to sub in a value for x into:  -x^2

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

    So would I do: -(4)^2 which gives -16, or

    would I do: (-4)^2 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
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    (Original post by Lid-the-squid)
    So I wanted to sub in a value for x into:  -x^2

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

    So would I do: -(4)^2 which gives -16, or

    would I do: (-4)^2 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
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    It would be -(x)^2 so -(4)^2 = -16
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    (Original post by Lid-the-squid)
    So I wanted to sub in a value for x into:  -x^2

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

    So would I do: -(4)^2 which gives -16, or

    would I do: (-4)^2 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

    Your reasoning is spot on
 
 
 
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