Is #f(x)=-x^5+3x^4-9x^3-2x^2-6x# concave or convex at #x=-3#?
1 Answer
Jan 4, 2016
*Answer could only be described as concave UPWARDS or DOWNWARDS (in your case, I'm not sure on how you view convex)
Answer: f''(-3) = 1022, hence, concave UPWARD
Explanation:
Method used: Second derivative test
Take the second derivative of f(x).
Then evaluate f(x) at x = -3
