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# Core 2 watch

1. A curve with equation y=f(x) such that
= 3x to the power of half - 2x to the power of minus a half and x>0.

a, Find the gradient of the curve at the point where x=2, giving your answers in its simplest form.
I substituted 2 in for x to get 3 - 2 = .
But, the mark scheme says that the answer is 2???
2. Have another look at what you get when you substitute x=2 - your version isn't quite right. Don't forget the minus in the second power!
3. (Original post by Pangol)
Have another look at what you get when you substitute x=2 - your version isn't quite right. Don't forget the minus in the second power!
i keep getting the same answer! what would you say 2 to the power of -1/2 then multiplied by 2 is?
4. 2 to the power of -1/2 is one over root 2, so you have 3 root 2 subtract 2 over root 2. You now have to rationalise the denominator of the second term before you can combine them.

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Updated: January 8, 2017
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