How can I multiply x with y? I mean I have to find AREA between function line and X-Axis.

Exercise is like this:

Function: y=tan(x/2) -> tan(x/2)

Determination area: 0,2<x<1,55

Code:#include<stdio.h> #include<math.h> #include<conio.h> int main() { float x,y,sum; for(x=0.2; x<1.55;x*tan(x/2)){ x = x + 0.0135*(x*tan(x/2)); y =tan(x/2); sum= printf("%f %f\n",x,y); } printf("Answer is: %f\n",sum); _getch(); return 0; }