1、课时作业(十五)一、选择题1.(x2x330)dx()A56B28C. D14答案C解析(x2x330)dx(4323)(4424)30(42).故选C.2若(2xk)dx2,则k等于()A0 B1C2 D3答案B3下列定积分值是0的是()A.xsinxdx B.x2cosxdxC.(x2x4)dx D.2(x35x5)dx答案D解析利用当f(x)是奇函数时,f(x)dx0当f(x)是偶函数时,f(x)dx2f(x)dx.4函数ycostdt的导数是()Acosx BsinxCcosx1 Dsinx答案A5 (1cosx)dx等于()A B2C2 D2答案D解析 (1cosx)dx2 (1co
2、sx)dx2(xsinx) 2(1)2.6若F(x)x2,则F(x)的解析式不正确的是()AF(x)x3BF(x)x3CF(x)x31DF(x)x3c(c为常数)答案B7.dx()A4 B6C3 D1答案A解析()(1x2)1(1x2),dx2dx22()4.故选A.8. dx等于()A8ln B8lnC16ln D16ln答案B解析dxxdxdxx2lnx(5232)ln5ln38ln,故选B.9mexdx与ndx的大小关系是()Amn Bmn.10(2010湖南高考) dx等于()A2ln2 B2ln2Cln2 Dln2答案D解析dxlnxln2.11.(exsinx)dx等于()Ae51
3、 Be52Ce53 De54答案C解析(exsinx)dxexdxsinxdxexcosxe5e0cos5cos0e5111e53.12(sinxdx)等于()Asinx BcosxCcosbsina D0答案D13.e|x|dx值等于()Ae2e2 B2e2C2e22 De2e22答案C二、填空题14假如f(x)dx1,f(x)dx1,那么f(x)dx_.答案2解析f(x)dxf(x)dxf(x)dx,1f(x)dx1.f(x)dx2.15已知函数f(x)3x22x1,若f(x)dx2f(a)成立,则a_.答案或1解析(x3x2x)3x22x1,f(x)dx(x3x2x)(111)(111)4.又2f(a)6a24a2,6a24a24,即3a22a10,解得a或a1.16设f(x)则f(x)dx等于_答案17若dx6,则b_.答案e4重点班选做题18(2011陕西)设f(x)若ff(1)1,则a_.答案11若F(x)满足F(x)sinx,则F(x)的解析式确定是()AF(x)cosxBF(x)cosxCF(x)1cosx DF(x)cosxc(cR)答案D解析由于(cosxc)(cosx)csinx0sinx,所以F(x)cosxc(cR)故选D.2求3(|2x3|32x|)dx.解析|2x3|32x| (|2x3|32x|)dx