求下列三角函数值(1)sin(-6/47π) (2)cos4/47π (3)tan(-3/17π)

问题描述:

求下列三角函数值
(1)sin(-6/47π)
(2)cos4/47π
(3)tan(-3/17π)

sin(-47/6π+8π)=1/2
cos(47/4π-12π)=√2/2
tan(-17/3π+6π)=√3/3