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# C1 Integration Exam Q watch

1. Dear TSR, I am lost as to the second step of the following question:

Given that y= 3x^1/2 - 4x^-1/2 (x>0)
(a) Find dy/dx
(b) Find ∫ydx.

I presumed that the second step was meant to prove the first step and simply integrated the answer from (a), but then checked the answer and was wrong. I have no clue what (b) actually wants me to do/find, as I haven't encountered ∫ydx as opposed to ∫(x^n)dx before.

If you could just tell me what to do to find ∫ydx that would be just as good if not better than actually going through this specific example... thanks.
2. (Original post by Philosopher-of-sorts)
Dear TSR, I am lost as to the second step of the following question:

Given that y= 3x^1/2 - 4x^-1/2 (x>0)
(a) Find dy/dx
(b) Find ∫ydx

I presumed that the second step was meant to prove the first step and simply integrated the answer from (a), but then checked the answer and was wrong. I have no clue what (b) actually wants me to do/find, as I haven't encountered ∫ydx as opposed to ∫(x^n)dx before.

If you could just tell me what to do to find ∫ydx that would be just as good if not better than actually going through this specific example... thanks.
Integrate y. . .
3. (Original post by Philosopher-of-sorts)
Dear TSR, I am lost as to the second step of the following question:

Given that y= 3x^1/2 - 4x^-1/2 (x>0)
(a) Find dy/dx
(b) Find ∫ydx.

I presumed that the second step was meant to prove the first step and simply integrated the answer from (a), but then checked the answer and was wrong. I have no clue what (b) actually wants me to do/find, as I haven't encountered ∫ydx as opposed to ∫(x^n)dx before.

If you could just tell me what to do to find ∫ydx that would be just as good if not better than actually going through this specific example... thanks.
Well, you know that y=3x^1/2 - 4x^-1/2, and you are asked to integrate y. So substitute:

∫ydx = ∫(3x^1/2 - 4x^-1/2)dx

...and there you have your ∫(x^n)dx form.
4. Just integrate y and you're done!
5. Bahaha that I just spent 20 minutes trying to integrate dy/dx to something strange and wondering what I was doing wrong because I can't read properly.

6. (Original post by Philosopher-of-sorts)
Bahaha that I just spent 20 minutes trying to integrate dy/dx to something strange and wondering what I was doing wrong because I can't read properly.

Happens to us all!
7. (Original post by Beth1234)
Happens to us all!
This!

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Updated: September 25, 2010
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