
Home > CALC > Chapter 8 > Lesson 8.3.3 > Problem 8-129
8-129.
Recall that candidates for points of inflection occur where the 2nd-derivative equals zero AND where the 2nd-derivative does not exist.
After you identify where f ''(x) = 0 and where f ''(x) = DNE, check the regions before, after and between those candidates: if f ''(x) > 0, then f(x) is concave up.