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cicelym
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Not to sound stupid but I was wondering if -½ is the same as -1/-2

And also, I was watching this indices revision video, and the person said 2x∧-3 = 2/x³ I would have thought 2x^-3 would be 1/2x^3 ?

This is the same for 3x²y∧-³ where they said it equals 3x²/y³
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BTAnonymous
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(Original post by cicelym)
Not to sound stupid but I was wondering if -½ is the same as -1/-2

And also, I was watching this indices revision video, and the person said 2x∧-3 = 2/x³ I would have thought 2x^-3 would be 1/2x^3 ?

This is the same for 3x²y∧-³ where they said it equals 3x²/y³
No, -½isn't the same as -1/-2 because -1/-2 equals a 0.5 because two negatives divided by each other equal a positive whereas -½ is equal to -0.5.

tbh I'm entirely sure but i think the negative sign applies to the whole answer of 1/2. So Although 1/2 = 0.5, the negative of 0.5 is obviously -0.5.

And the video seems to be wrong... I also agree 2x∧-3 is 1/2x^3.
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cicelym
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(Original post by BTAnonymous)
No, -½isn't the same as -1/-2 because -1/-2 equals a 0.5 because two negatives divided by each other equal a positive whereas -½ is equal to -0.5.

tbh I'm entirely sure but i think the negative sign applies to the whole answer of 1/2. So Although 1/2 = 0.5, the negative of 0.5 is obviously -0.5.

And the video seems to be wrong... I also agree 2x∧-3 is 1/2x^3.

Ah ok I see thank you
And this was the video I was watching if you skip to around 5.20 https://www.youtube.com/watch?v=mfrvdCngvq0
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abc_123_
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The guy in the video is correct. 2x^3 means

2 multiplied by x^-3 = 2 multiplied by 1/x^3
= 2/x^3

This is because only the 'x' is to the power of -3 the 2 is not to the power of -3 there is a separation between the 'x' and the 2 and according to BIDMAS the index (power) comes before the multiplication.

Hope this helped xx
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BTAnonymous
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(Original post by cicelym)
Ah ok I see thank you
And this was the video I was watching if you skip to around 5.20 https://www.youtube.com/watch?v=mfrvdCngvq0
Ahhh.... I see our mistake...

I guess the 1 which comes from x^-5 is because the coefficient of x is 1. Therefore, 2x^-3 is 2/3x^3 because the coefficient of x is 2. Well I've learnt another new thing today!
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