To be calculated with the accuracy of the term that after the absolute value is less than the size of 10^-5 on the interval [a,b] with step h , sum of the series 1-X^2/2!+X^4/4!-x^6/6!+x^8/8!-x^10/10! ... in C

Interval [a,b] : [Pi/ 12; 11Pi / 12]

Function: cosx