题目

Computers will already have becomemore handy and also (power) than human brains. 答案：【1】more powerful如图，P是∠BAC平分线上一点，PD⊥AC，垂足为D，以P为圆心，PD为半径作圆．（1）AB与⊙P相切吗？为什么？（2）若平行于PD的直线MN与⊙P相切于T，并分别交AB、AC于M、N，设PD=2，∠BAC=60°，求线段MT的长（结果保留根号）．