班级:学号:姓名:日期:月号1第六章定积分应用1判断题:(1)×(2)×(3)√(4)√(5)√2选择题:(1)A(2)C(3)C(4)C(5)B3填空题:(1)3/2(2)()()22'rrdβαθθθ⎡⎤+⎣⎦∫(3)4(4)3163a(5)2hshHρ⎛⎞−⎜⎟⎝⎠(6)213e−−4.'24,'(0)4yxy=−+=,切线43yx=−;'(3)2y=−,切线26yx=−+,故()()3322220094343d2643d4sxxxxxxxx=−+−++−++−+=∫∫.5.将(1,2)代入2yaxbx=+,得2ab=+,即2ba=−,求交点222(2)yxxyaxax⎧=−+⎪⎨=+−⎪⎩,知120,1axxa==+,故()()321201d61aaasaxaxxa+⎡⎤=+−=−⎣⎦+∫,()4322143'01,361aaasaaa++=−⋅=⇒=−=−+.经检验3a=−时,s最小,即3,5ab=−=时,s最小.6.cos1arctan,sinyxxyaxa=⎧⇒=⎨=⋅⎩cos1arctansinyxxybxb=⎧⇒=⎨=⎩,于是()1arctan210cossind1asxaxxaa=−=+−∫,1arctan22210arctansindcosd11bbsbxxxxbbπ=+=+−+∫∫,由于20cosd1sxxπ==∫,知1213ss==,故45,.312ab==7.由题意知()()()()()12d33dbasffxxsfxfxξξξξ=−==−∫∫,即证此式成立.设()()()()()322ddbbxaFxfxbxafxxfxx=−−−−∫∫,则()()()()()()()()3d,dbbaaFafabafxxFbfbbafxx⎡⎤=−−=−−⎢⎥⎣⎦∫∫.由中值定理可知,存在一()1,abξ∈使得()()()1dbafxxfbaξ=−∫,由于'()0fx>,可得()1()()faffbξ<<,故()()()()d()babafafxxbafb−<<−∫可知()()0,0FaFb<>.由连续函数零点存在定理可知,存在(),abξ∈使得()0Fξ=,从而123ss=.8.2001dd22xtsetxπ∞−⎛⎞=−=⎜⎟⎜⎟⎝⎠∫∫.9.223310sin3,3,d326arasrππππθθπθθ−====⇒==∫.班级:学号:姓名:日期:月号210.()230131ln2darctan2623srrrππ==+−∫.11.213dd22syxxya=−+=∫�.12.椭圆弧长为()()()()()()2222''2222100dsincosdsxtyttatbttππ=+=+∫∫;正弦曲线的一波之长为()()22222222001cosdsincosdbcxsxatbttbbππ⎛⎞=+=+⎜⎟⎝⎠∫∫,故12ss=.13.0,2sinlim12MNMNrMNrMNθθθ→=⋅=⋅⇒=.14.()()()()()()222222222222000''dsincosdd2aSxtyttattatttattπππ=+=+==∫∫∫.15.()()42233453'dln122srrθθθ=+⎡⎤=+⎣⎦∫.16.()122202d,32aabvaxbxabbsππ⎛⎞+=+=++=⎜⎟⎝⎠∫可得2242333bvssbπ⎛⎞=−+⎜⎟⎝⎠,故,0bsa==时,2minvsπ=.17.建立坐标变换1()21()2uxyvxy⎧=−⎪⎪⎨⎪=+⎪⎩,则2221xyuv−=⇒=,021323yxuxyvxyv=⇒=+=⇒=+=⇒=,故旋转体体积为32112d3vvvππ⎛⎞==⎜⎟⎝⎠∫.18.横截面积...