Originally Posted by
calc_help123 Hey i was having a problem with a hw problem
the function f(x)=(cosx)^2 +2cosx over one complete period begining with x=0
First we have to fun all values of x in this period when f(x)=0.
I know the period is 0-2π by looking at the graph however I dont know how to firgure it out analyitically though. So i found the zeroes but again i dont know how to do it analytically bc i am not got with sins and cos
Second we have to find all values of x in the period at which the function has a minimum.
3rd we have to find when the period is concave up but i dont know how to find the 2nd derivative of a cos