why can't the cosine of Pi divided by 2 equal zero?

Question

#include <iostream>

#include <cmath>

using namespace std;

int main()

{

const int PI = 3.14159;

cout << "cos(PI / 2) = " << cos(PI / 2) << "\n";

return 0;

}

Answer 1

because 3.14159 is not an int ... try this :
const double PI = 3.14159;

-Tom.

Comments

I tried that. It didn't give me "0" like it should, it just gave me a decimal number like 0.54. I also tried using all 14 data types associated with storing numbers to help out, none of them worked when I used them as constant variables.

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If I run this code with a const double, I get 1.32679e-06, which is pretty close to zero (this number stands for 0.00000132679). If you enter a number that is closer to the actual value of pi, with more decimals, you get even closer to zero. (But don't expect to ever get exactly zero; whatever you enter is just an approximation of pi.)
Hope this helps!

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i run your code, i get  0.540302 = cos(1)
because int PI = 3.14...  -> PI = 3
and cos(PI/2) -> cos(3/2) -> cos(1) because you are calculating integer values.

Answer 2

u can try this by using macros i.e. #define pi=3.14