tanx-6/secx+5在x趨向於∏/2時的極限

tanx-6/secx+5在x趨向於∏/2時的極限

lim(x→π/2)〔(tanx-6)/(secx+5)〕
=lim(x→π/2)〔sinx-6cosx)/(1+5cosx)〕
=(1-6×0)/(1+5×0)
=1