高考數(shù)學(xué)（理）二輪專題突破演練（浙江專版）第3部分 專題1 第2講“2道”拉分題專練卷2 Word版含解析

1、“2道”拉分題專練卷(二)1(2013溫州八校聯(lián)考)已知函數(shù)f(x)ex2x23x.(1)求曲線yf(x)在點(1，f(x)處的切線方程；(2)當x時，若關(guān)于x的不等式f(x)x2(a3)x1恒成立，試求實數(shù)a的取值范圍解：(1)f(x)ex4x3，則f(1)e1，又f(1)e1，曲線yf(x)在點(1，f(1)處的切線方程為ye1(e1)(x1)，即(e1)xy20.(2)由f(x)x2(a3)x1，得ex2x23xx2(a3)x1，即axexx21.x，a令g(x).則g(x).令(x)ex(x1)x21，則(x)x(ex1)x，(x)0，(x)在上單調(diào)遞增，(x)0，因此g(x)0，故g

2、(x)在上單調(diào)遞增，則g(x)g2.a的取值范圍是.2經(jīng)過點f(0,1)且與直線y1相切的動圓的圓心軌跡為m.點a、d在軌跡m上，且關(guān)于y軸對稱，過線段ad(兩端點除外)上的任意一點作直線l，使直線l與軌跡m在點d處的切線平行，設(shè)直線l與軌跡m交于點b、c.(1)求軌跡m的方程；(2)證明：badcad；(3)若點d到直線ab的距離等于|ad|，且abc的面積為20，求直線bc的方程解：(1)法一：設(shè)動圓圓心為(x，y)，依題意得，|y1|.整理，得x24y.所以軌跡m的方程為x24y.法二：設(shè)動圓圓心為p，依題意得點p到定點f(0,1)的距離和點p到定直線y1的距離相等，根據(jù)拋物線的定義可知

3、，動點p的軌跡是拋物線且其中定點f(0,1)為焦點，定直線y1為準線所以動圓圓心p的軌跡m的方程為x24y.(2)證明：由(1)得x24y，即yx2，則yx.設(shè)點d，由導(dǎo)數(shù)的幾何意義知，直線l的斜率為kbcx0.由題意知點a，設(shè)點c，b，則kbcx0，即x1x22x0.因為kac，kab，所以kackab0，即kackab.所以badcad.(3)法一：由點d到ab的距離等于|ad|，可知bad45.不妨設(shè)點c在ad上方，即x2x1，直線ab的方程為yx(xx0)由解得點b的坐標為.所以|ab|(x04)(x0)|2|x02|.由(2)知cadbad45，同理可得|ac|2|x02|.所以ab

4、c的面積s2|x02|2|x02|4|x4|20，解得x03.當x03時，點b的坐標為，kbc，直線bc的方程為y(x1)，即6x4y70.當x03時，點b的坐標為，kbc，直線bc的方程為y(x7)，即6x4y70.法二：由點d到ab的距離等于|ad|，可知bad45.由(2)知cadbad45，所以cab90，即acab.由(2)知kac，kab，所以kackab1.即(x1x0)(x2x0)16.由(2)知，x1x22x0.不妨設(shè)點c在ad上方，即x2x1，由解得所以|ab| 2|x02|，同理，|ac|2|x02|.以下同解法一高考資源網(wǎng)版權(quán)所有！投稿可聯(lián)系qq：10845918012

5、9c91afe4ced1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afedd1b6c87d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af95ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9d1b6c8795ad9c91afe4ced1b6c8795a1afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b

6、6c8795ad29c91afc91fe4ced1d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6cd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af8795ad9c91fe4ced1d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c87d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af5d1b6c8795

7、ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afad9c91fe4ced1b6c8795ad29c91afb6c8795ad29c91afb6c8795ad29c91afd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad

8、29c91affe4ced1b6c8795ad29c91afc8795ad9c91fe4ced1b6c8795ad29c91afd1b6c8795ad9c91afed1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8d1b6c8795ad9c91afe4ced1d91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afc91fe4ced1d1b6c871afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afc91fe4ced1d1b6c8795ad

9、9c91afe4ced1b6c8795ad91afe4ced1b6cd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af8795ad9c91fe4ced1d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c87d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af5d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c

10、8795ad9c91fe4ced1b6c8795ad29c91afad9c91fe4ced1b6c8795ad29c91afb6c8795ad29c91afb6c8795ad29c91afd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8791afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afc91fe4ced1d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ce

11、d1b6cd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af8795ad9c91fe4ced1d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c87d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af5d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c

12、91afad9c91fe4ced1b6c8795ad29c91afb6c8795ad29c91afb6c8795ad29c91afd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91affe4ced1b6c8795ad29c91afc8795ad9c91fe4ced1b6c8795ad29c91afd

13、1b6c8795ad9c91afed1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8d1b6c8795ad9c91afe4ced15ad9c91d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91affe4ced1b6c8795ad29c91afc8795ad9c91fe4ced1b6c8795ad29c91afd1b6c8795ad9c91afed1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8d1b6c879

14、5ad9c91afe4ced195ad9c91afe4ced1b6c8795ad91afe4ced1b6cd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af8795ad9c91fe4ced1d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c87d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af5d1b6c8795ad9c91afe4ced1b6c

15、8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afad9c91fe4ced1b6c8795ad29c91afb6c8795ad29c91afb6c8795ad29c91afd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91affe4ced1b6c

16、8795ad29c91afc8795ad9c91fe4ced1b6c8795ad29c91afd1b6c8795ad9c91afed1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af795ad9c91fe4ced1b6c8795add1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af29c91af4

17、ced1b6c8795ad1b6c8795ad9c91afe4ced1b6c8795ad91afd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afd1b6c8795ad29c91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afd91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c9d1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91af1afd1b6c8795ad9c91afe4ced1b6c8795ad91afe4ced1b6c8795ad9c91fe4ced1b6c8795ad29c91afd1