lingpw
幼苗
共回答了15个问题采纳率：86.7% 举报
sin（x-y）=0
sinxcosy- cosxsiny =0
cos（x+y）=0
cosxcosy-sinxsiny = 0
sinxcosy- cosxsiny = cosxcosy-sinxsiny
sinx-cosxtany= cosx- sinxtany
sinx-cosx= -tany(sinx-cosx)
(sinx-cosx)(1-tany)=0
sinx = cos x
x = 2kπ+ π/4
or tany = 1
or y = kπ + π/4
k=0,(+/-)1,(+/-)2,.
1年前
10
