what is cosh?? also can someone help solve this problem: let f(x)= cosh(x)= (e^x - e^-x)/ 2 :

a. at what x-values does f have relative extrema?

b. find the exact value of the integration of f(x)dx from 1 to -1

c. show that f does not have any points of inflection.

any help would be good; not asking for direct answers that those would not hurt. thanks a bunch!!

*dnt just view ppl! lol