① 若<imgwidth="54"height="20"v:shapes="_x0000_i1352"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image297.png">有解,则必有<imgwidth="54"height="22"v:shapes="_x0000_i1353"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image439.png">
② 若<imgwidth="54"height="20"v:shapes="_x0000_i1354"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image297.png">无解,则必有<imgwidth="54"height="22"v:shapes="_x0000_i1355"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image441.png">
③ 若<imgwidth="54"height="20"v:shapes="_x0000_i1356"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image297.png">有非零解,则必有<imgwidth="54"height="22"v:shapes="_x0000_i1357"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image439.png">