1. ## Curve, gradient and point.

a - ( (b) / (c+x^2) )

The line goes through (2, $2/3$) and the gradient of the curve is at its maximum at x= root6/3 (square root of 6 divided by 3)

Prove a = 1, b = 2, c = 2.

Can I please have a detailed solution to this? I've tried so many ways, been hours already. It was in the dydx and integration section.

2. ## Re: Help!

sorry c wasnt 3, c = 2

3. ## Re: Help!

For example, if the curve goes throught the point $\left(2,\frac{2}{3}\right)$ that means:
$\frac{2}{3}=a-\frac{b}{c+4}$

Have you tried something this way? Also with the other given information? ...

4. ## Re: Help!

Yes I was aware it was a curve. I've tried something like that. Still ended up with 2 unknowns. and 3 in the other.

And the point where the gradient is its max. Stuck on how to get that equation. Or use that info. Would it be double derivative?

5. ## Re: Help!

Yes, calculate the second derivative of the function, then let $f''(x)=0$ and enter $x=\frac{\sqrt{6}}{3}$ therefore you can calculate $c$.