I need help with question 12 and 13. I kind of know how to do it but I just need steps to it

Safari File Edit View History Bookmarks Window Help ! 64% Tue 9:49 PM .. . G piazza.com Sy P P U UU U Homework Help - Q&A from Online Tutors - Co.. Favorites Favorites (U = U PARTICIPATION ACTIVITY 3.2.5: Contin.. + -5- -5 0 5 -5. 12. (a) Determine the intervals on which f(x) = 2x3 - x2 - 20x + 1 is increasing and decreasing. (b) Determine the intervals on which f(x) = In(x2 + 4) is concave up and concave down. 13. (a) Find a function F(x) such that F'(x) = 1 + 2 sinx + 3vx + 5e" and F(0) = 10. (b) An object has velocity function v(t) = 2 + 6t + 4et and initial position s(0) = 9. What is its position function s (t) ? 14. The following is a graph of y = f (x): DEC 17 .... OXWd