For what values of x is #f(x)=(x-1)(x-7)(x-1)# concave or convex?
Convex if x is greater than 1.5, concave if less than 1.5
A function is convex (aka concave up) when
Now we differentiate using the power rule...
And once more...
We then find when this is greater than 0...
This, the function is convex for x greater than 1.5, concave for x less than 1.5