f(x)=sin(2x-5/2Л)=sin(2x-π/2)=-cos2x
f(-x)=-cos(-2x)=-cos2x=f(x)
所以 y=sin(2x-5/2Л)是偶函数
g(x)=sin(3x-Л/4)
g(π/4)=sin(3π/4-π/4)=sin(π/2)=1
g(-π/4）=sin(-3π/4-π/4)=sin(-π)=0
所以 g(-x)=g(x)不成立,g(-x)=-g(x)也不成立
所以 y=sin(3x-Л/4)是非奇非偶函数
判断函数y=sin(2x-5/2Л),y=sin(3x-Л/4),的奇偶性~