曲线<img src="/lqwvjeImg/b9/b9e17f94de9d5d08104d0c185003d23f.png"style="width:43px;height:24px;">的拐点坐标是( )。<br>·<img src="/lqwvjeImg/5e/5e0797f99ad49c40b11648edd76ee5d2.png"style="width:81px;height:33px;">;<br>·<img src="/lqwvjeImg/d1/d114fe6f27e79e59477e248992f305bc.png"style="width:37px;height:21px;">;<br>·<img src="/lqwvjeImg/f3/f369c91306462a359bb11b5cc7bd8dea.png"style="width:32px;height:21px;">;<br>·<img src="/lqwvjeImg/0e/0e675fee3d369a4a05170ddb37c3b4b0.png"style="width:37px;height:21px;">。