Index, logarithm, etc. in C + +

C + + has a ready-made header file, #include <cmath> after adding it, you can use exp () to represent the natural logarithm e index, log () is used to find the logarithm, and

_std_begin
Using _cstd ACOSF using _CSTD asinf;
using _CSTD atanf; using _cstd atan2f; using _cstd Ceilf;
Using _CSTD COSF; Using _CSTD COSHF; Using _CSTD EXPF;
using _CSTD fabsf; using _cstd Floorf; using _CSTD fmodf;
using _CSTD frexpf; using _cstd ldexpf; using _CSTD logf;
using _CSTD log10f; using _cstd modff; using _CSTD POWF;
using _CSTD sinf; using _cstd sinhf; using _CSTD sqrtf;
using _CSTD tanf; using _CSTD TANHF;


using _CSTD acosl; using _cstd asinl;
using _CSTD atanl; using _cstd atan2l; using _cstd Ceill;
Using _CSTD COSL; Using _CSTD COSHL; Using _CSTD expl;
using _CSTD fabsl; using _cstd floorl; using _CSTD fmodl;
using _CSTD frexpl; using _cstd ldexpl; using _CSTD logl;
using _CSTD log10l; using _cstd MODFL; using _CSTD powl;
using _CSTD sinl; using _cstd sinhl; using _CSTD Sqrtl;
using _CSTD tanl; using _CSTD tanhl;