cos(a-b/2)=-3/5,sina(a/2-b)=5/13,且派>a>二分之派,0

问题描述:

cos(a-b/2)=-3/5,sina(a/2-b)=5/13,且派>a>二分之派,0

cos(a-b/2)=-3/5,sina(a/2-b)=5/13,且派>a>二分之派,0