1-(x^2/2!)+(x^4/4!)-(x^6/6!)+...+(-1)^n*(x^2n/(2n)!)
what is f'''''(0) = ? (f^(5)(0))
what is f''''''''''(0) = ? f^(10)(0)
I have no ideas how to approach this.. please help...
更新1:
can anyone also answer my other question? https://ca.answers.yahoo.com/question/index?qid=20150405143448AAkB25i