计算:sin(3π /4 ) +cos (2π /3) - sin 150° + cos135°=?
问题描述:
计算:sin(3π /4 ) +cos (2π /3) - sin 150° + cos135°=?
答
sin(3π/4)+cos(2π/3)-sin150°+cos135°
=(√2/2)-(1/2)-(1/2)-(√2/2)
=-1