a) Write a c++ program using function to calculate cos(x) from the formula cosx=121x2+41x262x3+=n=0(27x)2(1)mx2x. b) another program using function to calculate tan(x) from the formula tanx=x+31x3+152x5+31517x7+. C) Other program using function to calculate tan(x) from the formula sinx=x3!x3+5!x57!x7+=n=0(2n+1)!(1)nx2n+1 d) other program using function to calculate ex from the formula ex=1+x+2!x2+3!x3+4!x4 2)a) Write a c++ program using function to calculate factorial of any integer use to calculate y=sinx in formula I=Tz!(12Mz)!12! b) Another program using cosx from previous formula c) Another program using tanx from previous formula