设<imgwidth="32"height="21"v:shapes="_x0000_i1056"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb07.files/image046.png">为两个随机事件,且<imgwidth="73"height="21"v:shapes="_x0000_i1057"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb07.files/image048.png">,则<imgwidth="80"height="21"v:shapes="_x0000_i1058"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb07.files/image050.png">()
①
<imgwidth="37"height="21"v:shapes="_x0000_i1059"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb07.files/image052.png">
②
<imgwidth="48"height="21"v:shapes="_x0000_i1060"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb07.files/image054.png">
③
<imgwidth="66"height="21"v:shapes="_x0000_i1061"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb07.files/image056.png">