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# Need help with differentiation (as level) watch

1. Differentiate
y= (4-x) / (2+root x)
i've made root x power of 1/2
then i seperated the equations
(4 / 2x^1/2) - (x / 2+x^1/2)
then i simplified them to get
(2/root x) - (1/2x^1/2)
i then differentiated dy/dx to get this
(-x^-3/2) - (1/4x^-1/2)
which is wrong
2. (Original post by AsianG99)
Differentiate
y= (4-x) / (2+root x)
i've made root x power of 1/2
then i seperated the equations
(4 / 2x^1/2) - (x / 2+x^1/2)
then i simplified them to get
(2/root x) - (1/2x^1/2)
i then differentiated dy/dx to get this
(-x^-3/2) - (1/4x^-1/2)
which is wrong
Well, you differentiated correctly, but everything before that was wrong. You really need to brush up on your algebraic manipulation.

As to the given question, I suggest multiplying the top and bottom by to simplify it.

Also, you might want to start using LaTex - guide in Useful Resources widget; that's barely readable.
3. (Original post by ghostwalker)
Well, you differentiated correctly, but everything before that was wrong. You really need to brush up on your algebraic manipulation.

As to the given question, I suggest multiplying the top and bottom by to simplify it.

Also, you might want to start using LaTex - guide in Useful Resources widget; that's barely readable.
Ahh i see now
I didn't rationalise the denominator
Just started doing differentiation in my class

Thanks!

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