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# Differentiation watch

1. (Original post by RichE)
No it isn't. There are rules for which operations to do first and you need to use brackets if you want operations to be done in a different order.
Its called the reciprocal, to get rid of a negative power you do 1 over the term with the positive power,
2x^-3 = 1/2x^3
2. Here is my go at it.
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3. (Original post by HiggsBoson)
Its called the reciprocal, to get rid of a negative power you do 1 over the term with the positive power,
2x^-3 = 1/2x^3
You're still wrong.

2x^-3 means 2/(x^3).

1/2x^3 means (1/2) (x^3)

To get what you want you should write

1/(2x^3) or (2x^3)^(-1).

Look up BIDMAS if necessary. This is pre-GCSE stuff.
4. (Original post by HiggsBoson)
Its called the reciprocal, to get rid of a negative power you do 1 over the term with the positive power,
2x^-3 = 1/2x^3
Pretty sure that would be 2/x^3
5. (Original post by RichE)
You're still wrong.

2x^-3 means 2/(x^3).

1/2x^3 means (1/2) (x^3)

To get what you want you should write

1/(2x^3) or (2x^3)^(-1).

Look up BIDMAS if necessary. This is pre-GCSE stuff.
OK, I understand the confusion with 1/2x^3, but 2x^-3 mean 2x to the power 3, I don't see any reason to be confused with this.
6. (Original post by The Night King)
Pretty sure that would be 2/x^3
7. (Original post by HiggsBoson)
OK, I understand the confusion with 1/2x^3, but 2x^-3 mean 2x to the power 3, I don't see any reason to be confused with this.
Did you mean to write that?

And if you meant to write "2x to the power -3" what do you mean by that

(2x)^(-3) or 2/x^3

as they are different things?
8. (Original post by RichE)
Did you mean to write that?

And if you meant to write "2x to the power -3" what do you mean by that

(2x)^(-3) or 2/x^3

as they are different things?
They equal each other though, 2/x^3 is just simplified.
9. (Original post by HiggsBoson)
They equal each other though, 2/x^3 is just simplified.
No they aren't equal - you need to remember your power rules

(2x)^(-3) = 2^(-3) * x^(-3) = (1/8) x^(-3)
10. (Original post by RichE)
No they aren't equal - you need to remember your power rules

(2x)^(-3) = 2^(-3) * x^(-3) = (1/8) x^(-3)
Oh Ok i get what you mean

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