『急求』1/2sin2x+1/2cos2x怎么等于√2/2sin(2x+π/4)
问题描述:
『急求』1/2sin2x+1/2cos2x怎么等于√2/2sin(2x+π/4)
1/2sin2x+1/2cos2x怎么等于√2/2sin(2x+π/4) 需要详细过程.
sinxcosx+cosx^2-1/2
=1/2sin2x+1/2cos2x
=√2/2sin(2x+π/4)
希望能把sinxcosx+cosx^2-1/2怎么等于1/2sin2x+1/2cos2x也一起写上
答
=√2/2(√2/2cos2x+√2/2sin2x)
=√2/2(sinπ/4cosπ/4+sinπ/4cosπ/4)
=√2/2sin(2x+π/4)