PHP 忒聊 綴豖 ヶ輛 acos (PHP 3, PHP 4) 鏡扴 殿隙 arg 腔毀豻玾硉ㄛ等弇岆說僅﹝ acos() 岆 cos() 腔毀滲杅ㄛ坳腔砩佷岆婓 acos() 毓峓爵腔藩跺硉飲岆 a==cos(acos(a)) ﹝ See also acosh(), asin() and atan(). 綴豖 れ萸 ヶ輛 abs 奻珨撰 acosh