How do you take the sin of a function in c++?

I am trying to perform sin(pi*0.5), but I cant get it to work. Here is my code:


#include%26lt;iostream%26gt;


#include%26lt;math.h%26gt;


using namespace std;


const double PI = 4.0*atan(1.0)


int main()


{


x = sin( pi*0.5 );


cout %26lt;%26lt; x;


}


It will not give the correct answer. Any help?

How do you take the sin of a function in c++?
error 1 -- x should be declared like





double x;





error 2 -- there is a ; at the end of const double ...





error 3 -- the const is PI all caps.





It works on my machine.