x=π/4 时,sinπ/4 =cosπ/4,∴分母为0
则:x不能取π/4;
x=﹣π/4 时,sinπ/4 =﹣√2/2 cosπ/4=√2/2 ∴分母不为0
则:x 能取﹣π/4
综上,函数的定义域不对称,所以是非奇非偶函数