考试大礼包有限元版第三章

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7、,/92bcdzej ufC2(0, L)bF !#$%qrZ9%ygvhZ#L:9GA u(x)h0j/ej ufH|(0, L)1M h5EHJKK0Zij-% a9k % t9)RD/H (fx, fy), AB 45y, vnq(x)P(x) BCCD AD 21(EH% q(x)9l(EH% p(x) #P &mnef%s12 E nTnu, vtdxdyPuT f x tdxdy f y v x, uuT p v q tdxAD $ XYX1H1 %8cdzh0j/2yzGH2yzoT9C2 %bcdz/92yzGH2yzoT+ 3 ,- 17 ,AD(fx, fy)BOCnupA

8、B=vpAB=0QFT x0 u T E T E T E 0 x 112E T y v y 2 xy yx kRsQdxdy d xL dsxdyxXdxdy d yL dsxdyYyI= LX#LY %ijt7(2=1u n 20(vw#P 2x*ef%suT f xuT p1 T E P ( 2 tdxdy) v v tdxdy q tdx fAD y T0 TuT x x LX0 u x f 0 x tdxdy 0Ly tdsy fY v y vy LL XY yx yx x yuT pq tds 0(3-1-5)vAD xIRy(9=1u n 20(vw%kRyu ABs$u=$v=0

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10、Rar78mnef $v(0)=$v/(0)=0M,L EIv q vdx ) M vL EIv(LP0 EIv Q (v(3-1-7) L0 x L:(3-1-7)HI$v(x) SH?2FrGef+sEIv q 0EIv(L) M 0hi0tEIvfef Q 0 x LY0t2cz% %a vv 2ef%fef9%a vv 2e f%mneftu/*STWXv v(x)4wxAyznv|C4(0,L)u#$%&(WXvCb1& 2C! v(x)DSOv|H2(0,L)l!28g#K9jj%zNG9czNG2#O$%8&Gt()DnOI=9|Y0tcz*+kab%kl+,*9)-9|jY,G

11、A*+1 (0) 1 (L) 2 (0) 2 (L) 0v 11 (x) 2 2 (x)%23yz91 ,1 %5Yz9Mqr;8JK2#*w6yjWH1 LL33 EI (v ) dx P v() 2EIL(1 1 2 L 2 L ) 242L L22223P1216640#*6y2x*efP 0P 0, 21R8#z0tG3 PL4 2L 1216 EI3 PL2 4L 1264 EI#z0tG23yz=25Yz 7 PL ,128 EI 1 P 64 EI12=#ab2O_*%PL3Lv( ) 0.00952 4EI+ 6 ,- 17 ,1MsH,-mnb%mn (x) sin 2 x

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15、.0 11xT./9%Ubaw3#2ijtqq%5g././&! Nh|kyz0685 kyz 1(x,y)b 9(x,y)78i i(xj,yj)=(ij1 j=iM0 ji(ii) i(x,y):&g./5+xy 2u,yzM23yz9u( x, y) uiii1v(x, y) viii 1ef i(xj,yj) 25 9:#6,X7=u(xi , yi ) uiv(xi , yi ) viVz uivi h%#62ab*:&g./59uv + xy 2?Z8ONOQ9jk8g#62yz*8m59 jKb22-3-2OF:f:./5 uv /99;Idzuxuyvxvy%Yzy./#D i

16、j 9uv Au,h9?Z;e6Xg #62yz* uiviujvj Ev 59BC./Z uv /9D$ 3-11 EFxC./ZIu,vdzuxuyvxvy8N/99,-2DE*9x:t5S?h0j/ E0223yz78h5EHJKbcJK_,&jY,2GAjF Ritz 1AO_Xv#K52abFWHix$3-11u U v u9 v 9 F8g./, 6 gI=)%8g 2G18 2-0Eq9):8g./5,|M# 9b6Q+ 18 g 7JK2v#yzjkOP%uT 01 T E tdxdy 2 tdx Pv q ADuT 0128 e vT tdxd qtdxAD i1i+ 12

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18、23yzPRRJKlJ2Pom?ZQd9Bb,-/8S+O_RS:TqUUpV./W &-h!Z,-/efcdRPo%ygvcd,9(./5K52abF23yzE78kn|28A9:32N$Oyz;+ !#$%EGA29R+P6QRR2M&4WX56(Vty1*7kt89l()?;8ef2%+s./&-XZ9Po:&g./5SYOZMYEhWD%,-/&-YOv#2Po !*97R# OyPo78;8ef28gMD+9D%Po:/gij6%8YEhWP_EHhLha9bcdW 2./Lu?mPM2O_X:;64A:+:K5./abFZN34abefefmnef9;&ef:GovDEqZgpk34D%./abFhmZMpbiQ9ojIkyp6yl=2efVHo$efM&X+N2a()*+9Gn?Z8ONOQuxu 1 2 xLjI=51 %pDhb952x %YEhO 2ah5EHJK9on xy 2?Z8ONOQLj9L 5 3x 3 5u x y y y 123122 5 32 v x y y x x 354564622+ 14 ,- 17 ,I=K8gpa5%8gpDabsbghb8gqxKbgpa5%YEhOW u v u v