Question....

[ElephantStew]

hey guys, i've been having trouble with this problem for some time:

The curve with the equation passes through (0,7) and has a stationary point at (2,15). Find a, b and c.

Thank you.

[orangez]

Hey ElephantStew, I can't really use LaTeX, but I'll describe the process of solving this equation:

1. let (x,y) = (0,7) and from this you should get c = 7
2. Now sub in the coordinate (2,15)
3. Differentiate the equation. We know that at stat. points, the gradient equals 0 -- and we also know that it exists at x = 2 ==> let x = 2, dy/dx = 0
4. You'll end up getting simultaneous equations, therefore you can figure out a & b

Hope this helps!