sin π /2 ×cos π/2-tg π/3×ctg π/3 谁会作
问题描述:
sin π /2 ×cos π/2-tg π/3×ctg π/3 谁会作
答
sin π /2 ×cos π/2-tg π/3×ctg π/3
=1*0-1
=0