A:y=x+cosx
B:y=x+sinx
C:y=x
D:y=e﹣|x|
—Would you like to visit Taiwan with me this summer holiday?
—_____________. Because my family plan to go to another place.
对于定义在R上的奇函数fx,满足fx+3=fx,则f1+f2+f3=( )