関連ワード:  is cosine an even or odd function    is cos an even or odd function    is sin an even or odd function    is cosx an even or odd function    is sin x an even or odd function    is sin 2x an even or odd function    is sin^2 an even or odd function    is sin x cos x an even or odd function    is y=cos/x an even or odd function    is sin x even or odd function