View Compilation Error

0_0_30139010_7141.cpp: In function 'double func(double)':
0_0_30139010_7141.cpp:7:22: error: 'pow' was not declared in this scope
  return (8 * pow(x, 4) + 7 * pow(x, 3) + 2 * pow(x, 2) + 3 * x + 6);
                      ^
0_0_30139010_7141.cpp: In function 'int main()':
0_0_30139010_7141.cpp:41:30: error: 'pow' was not declared in this scope
   else if (Y > 8 * pow(100, 4) + 7 * pow(100, 3) + 2 * pow(100, 2) + 3 * 100 + 6)
                              ^