using ::abs; //絕對值　　using ::acos; //反餘弦　　using ::acosf; //反餘弦　　using ::acosl; //反餘弦　　using ::asin; //反正弦　　using ::asinf; //反正弦　　using ::asinl; //反正弦　　using ::atan; //反正切　　using ::atan2; //y/x的反正切　　using ::atan2f; //y/x的反正切　　using ::atan2l; //y/x的反正切　　using ::atanf; //反正切　　using ::atanl; //反正切　　using ::ceil; //上取整　　using ::ceilf; //上取整　　using ::ceill; //上取整　　using ::cos; //餘弦　　using ::cosf; //餘弦　　using ::cosh; //雙曲餘弦　　using ::coshf; //雙曲餘弦　　using ::coshl; //雙曲餘弦　　using ::cosl; //餘弦　　using ::exp; //指數值　　using ::expf; //指數值　　using ::expl; //指數值　　using ::fabs; //絕對值　　using ::fabsf; //絕對值　　using ::fabsl; //絕對值　　using ::floor; //下取整　　using ::floorf; //下取整　　using ::floorl; //下取整　　using ::fmod; //求餘　　using ::fmodf; //求餘　　using ::fmodl; //求餘　　using ::frexp; //返回value=x*2n中x的值,n存貯在eptr中　　using ::frexpf; //返回value=x*2n中x的值,n存貯在eptr中　　using ::frexpl; //返回value=x*2n中x的值,n存貯在eptr中　　using ::ldexp; //返回value*2exp的值　　using ::ldexpf; //返回value*2exp的值　　using ::ldexpl; //返回value*2exp的值　　using ::log; //對數　　using ::log10; //對數　　using ::log10f; //對數　　using ::log10l; //對數　　using ::logf; //對數　　using ::logl; //對數　　using ::modf; //將雙精度數value分解成尾數和階　　using ::modff; //將雙精度數value分解成尾數和階　　using ::modfl; //將雙精度數value分解成尾數和階　　using ::pow; //計算冪　　using ::powf; //計算冪　　using ::powl; //計算冪　　using ::sin; //正弦　　using ::sinf; //正弦　　using ::sinh; //雙曲正弦　　using ::sinhf; //雙曲正弦　　using ::sinhl; //雙曲正弦　　using ::sinl; //正弦　　using ::sqrt; //開方　　using ::sqrtf; //開方　　using ::sqrtl; //開方　　using ::tan; //正切　　using ::tanf; //正切　　using ::tanh; //雙曲正切　　using ::tanhf; //雙曲正切　　using ::tanhl; //雙曲正切　　using ::tanl; //正切