若sinθ=(m-3)/(m+5),cosθ=(4-2m)/(m+5),求m的取值?
问题描述:
若sinθ=(m-3)/(m+5),cosθ=(4-2m)/(m+5),求m的取值?
如题~
答
因为(sinx)^2+(cosx)^2=1,
所以(m-3)^2/(m+5)^2+(4-2m)^2/(m+5)^2=1,
解得m=0或8.