函数y=sin²(x+π/12)+cos²(x-π/12)-1的周期T=?,奇偶性为
函数y=sin²(x+π/12)+cos²(x-π/12)-1的周期T=?,奇偶性为
日期:2009-01-21 17:48:21 人气:1
答案:T=π 奇函数
解答:y=1-(cos(x+π/12))^2+(cos(x-π/12))^2-1
=(cos(x-π/12))^2-(cos(x+π/12))^2
=(cos(x-π/12)-cos(x+π/12))×(cos(x-π/12)+cos(x+π/12))
=2cosxcosπ/12×2sinxsinπ/12
=(2sinxcosx)×(2sinπ/12cosπ/12)
=s