今天考试的最后一题我哪里错了
我觉得我应该错了而且错的很离谱<br />但是一直没检查出来<br />图片和文档过程都在附件<br /><br />[ 本帖最后由 zhangyuong 于 2007-12-22 23:11 编辑 ]<br> 你，初三？<br> 是的<br />为了解题迅速我用了解析几何<br> yun没人来呢<br> 自变量x的取值范围求错了，上界没问题，下界是x大于或等于根号3，忽视了y小于或等于4<br> 明白了谢谢小南老师<br />可为什么我算下限<br />是9-(x-√3)^2<=9<br />这里x解出是全体实数呢<br /><br />[ 本帖最后由 zhangyuong 于 2007-12-23 14:07 编辑 ]<br> 你那个不等式x的取值范围是全体实数没错，但你没考虑到那个式子中x－√3必须是非负数，因为这是一条线段的长度，当MP与x轴垂直时这条线段退化成一个点可认为距离为0<br> 饿应该是这样~~<br />这种题我还是第一次见呢<br />还要考虑几何意义<br> 下界x≥√3有误吧？？？<br> 过程复杂。<br> <br><br>QUOTE:原帖由 白衣飘雪 于 2007-12-23 17:10 发表 <a href="http://bbs.pep.com.cn/redirect.php?goto=findpost&pid=3542850&ptid=346802" target="_blank"><img src="http://bbs.pep.com.cn/images/common/back.gif" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt='Click here to open new window\nCTRL+Mouse wheel to zoom in/out';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor='hand'; this.alt='Click here to open new window\nCTRL+Mouse wheel to zoom in/out';}" onclick="if(!this.resized) {return true;} else {window.open(this.src);}" onmousewheel="return imgzoom(this);" alt="" /></a><br />下界x≥√3有误吧？？？ <br>不好意思，的确是我错了<br> 饿<br />请白衣飘雪老师指导<br />除了那里还有哪里错了<br> 如图：<br />1、先找到动圆的两个极端位置，再确定P点的运动范围<br />2、无需用到y来求解<br />3、考虑极端位置时的∠OM0P0的大小来判断，若存在还是要用到相似来求x值。<br /><img src="http://bbs.pep.com.cn/attachments/20071223_433bf0cb468da4eeb73bxhozPqgBVe9C.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt='Click here to open new window\nCTRL+Mouse wheel to zoom in/out';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor='hand'; this.alt='Click here to open new window\nCTRL+Mouse wheel to zoom in/out';}" onclick="if(!this.resized) {return true;} else {window.open(this.src);}" onmousewheel="return imgzoom(this);" alt="" /><br /><img src="http://bbs.pep.com.cn/attachments/20071223_5ca4432f0c24a5d8c173FHtdjT6qkJc3.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt='Click here to open new window\nCTRL+Mouse wheel to zoom in/out';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor='hand'; this.alt='Click here to open new window\nCTRL+Mouse wheel to zoom in/out';}" onclick="if(!this.resized) {return true;} else {window.open(this.src);}" onmousewheel="return imgzoom(this);" alt="" /><br /><br />[ 本帖最后由 白衣飘雪 于 2007-12-23 20:21 编辑 ]<br>页:
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