math:sin/1
求正弦值
用法：
sin(X)
返回一个数字的正弦值
Sin = math:sin(45),
io:format("Sin is ~p~n", [Sin]).
Pi = math:pi(),
Sin = math:sin(Pi / 2),
io:format("Sin is ~p~n", [Sin]).
求正弦值
用法：
sin(X)
返回一个数字的正弦值
Sin = math:sin(45),
io:format("Sin is ~p~n", [Sin]).
Pi = math:pi(),
Sin = math:sin(Pi / 2),
io:format("Sin is ~p~n", [Sin]).