已知⊙O的直径AB的长为4㎝,C是⊙O上一点,∠BAC=30°,过点C作⊙O的切线交AB的延长线于点P,求BP的长
(绵阳)计算:.
(眉山)(本小题满分6分)计算:.
(泸州)计算:.
(泸州)化简:.