填空题
13．求sin72°的按键顺序是_________．
14．求tan25°42°的按键顺序是__________．
15．求cot32°19′的按键顺序是__________．
16．用计算器cos18°44′25″=__________．
填空题
13．求sin72°的按键顺序是_________．
14．求tan25°42°的按键顺序是__________．
15．求cot32°19′的按键顺序是__________．
16．用计算器cos18°44′25″=__________．