Question

下列函數(shù)圖象關(guān)于原點(diǎn)對(duì)稱的有（     ）
①；②；
③④.

A．①②

B．①③

C．②③

D．②④

Answer 1

D

試題分析：在函數(shù)①的定義域?yàn)?img src="http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824025820927392.png" style="vertical-align:middle;" />，值域?yàn)?img src="http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824025820943408.png" style="vertical-align:middle;" />，所以函數(shù)圖像為只有一個(gè)點(diǎn)，不關(guān)于原點(diǎn)對(duì)稱；在函數(shù)②定義域?yàn)?img src="http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824025820974303.png" style="vertical-align:middle;" />，且函數(shù)為奇函數(shù)，所以其圖像關(guān)于原點(diǎn)對(duì)稱；在函數(shù)③的定義域?yàn)?img src="http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824025821005648.png" style="vertical-align:middle;" />不關(guān)于原點(diǎn)對(duì)稱；函數(shù)④的定義域?yàn)?img src="http://thumb.zyjl.cn/pic2/upload/papers/20140824/20140824025821021580.png" style="vertical-align:middle;" />，且函數(shù)為奇函數(shù)，所以其圖像關(guān)于原點(diǎn)對(duì)稱.所以正確答案為D.