View Compilation Error

0_0_12935253_27084.cpp: In function `double f(double)':
0_0_12935253_27084.cpp:12: error: `sqrt' undeclared (first use this function)
0_0_12935253_27084.cpp:12: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_12935253_27084.cpp: In function `double work(double, double, double)':
0_0_12935253_27084.cpp:24: error: `fabs' undeclared (first use this function)