cos(-585°)/sin495°+sin(-570°)的值是

来源:学生作业帮助网 编辑:六六作业网 时间:2024/10/06 11:22:02
cos(-585°)/sin495°+sin(-570°)的值是cos(-585°)/sin495°+sin(-570°)的值是cos(-585°)/sin495°+sin(-570°)的值是cos(

cos(-585°)/sin495°+sin(-570°)的值是
cos(-585°)/sin495°+sin(-570°)的值是

cos(-585°)/sin495°+sin(-570°)的值是
cos(-585°)/sin495°+sin(-570°)
=cos585°/sin495°-sin570°
=cos(540+45)/sin(540-45)-sin(540+30)
=-cos45/sin45+sin30
=-1+1/2
=-1/2