计算 sin5π/8*cos(7/8)π+sinπ/8-cos(3/8)π

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/23 18:49:17
计算sin5π/8*cos(7/8)π+sinπ/8-cos(3/8)π计算sin5π/8*cos(7/8)π+sinπ/8-cos(3/8)π计算sin5π/8*cos(7/8)π+sinπ/8-c

计算 sin5π/8*cos(7/8)π+sinπ/8-cos(3/8)π
计算 sin5π/8*cos(7/8)π+sinπ/8-cos(3/8)π

计算 sin5π/8*cos(7/8)π+sinπ/8-cos(3/8)π
sin5π/8*cos(7/8)π+sinπ/8cos(3/8)π
=-sin3/8π*cos(1/8)π+sinπ/8cos(3/8)π
=sinπ/8cos(3/8)π-sin3/8π*cos(1/8)π
=sin(π/8-3/8π)
=sim(-π/4)=-根号下2/2