5.计算下列二重积分:-|||-(1) iint y[ 1+x(e)^dfrac (1{2)((x)^2+(y)^2)}] dxdy, 其中D是由直线 =x, y=-1 及 x=1 围成的平面区域;-|||-(2) (iint )_(D)^int (x+y)dxdy, 其中 :(x)^2+(y)^2leqslant x+y+1;-|||-(3) (iint )_(b)(sqrt ({x)^2+(y)^2}+y)dx, 其中D是由圆 ^2+(y)^2=4 和 ((x+1))^2+(y)^2=1 所围成的平面区域;-|||-(4) int (x)^2+(y)^2-4|dsigma , 其中 :(x)^2+(y)^2leqslant 9;-|||-(5) iint dfrac (1+xy)(1+{x)^2+(y)^2}dxdy 其中 = (x,y)|{x)^2+(y)^2leqslant 1,xgeqslant 0} ;-|||-(6) (iint )_(0)^max(x)^2,(y)^2dxdy, 其中 = (x,y)|0leqslant xleqslant 1,0leqslant yleqslant 1 ;-|||-(7) (int )_(-infty )^+infty (int )_(-infty )^+infty min x,y (e)^-((x^2+{y)^2)}dxdy;-|||-(8) iint ((x+y))^3dxdy, 其中D由曲线 =sqrt (1+{y)^2} 与直线 +sqrt (2)y=0 及 -sqrt (2)y=0 围成;-|||-(9) iint xy[ 1+(x)^2+(y)^2] dxdy, 其中 = (x,y)|{x)^2+(y)^2leqslant sqrt (2),xgeqslant 0,ygeqslant 0} [ 1+(x)^2+(y)^2] 表示不超-|||-过 https:/img.cdnjtzy.com/zyb_1b00c8eeba2423353038c79b7ca7d269.jpg+(x)^2+(y)^2 的最大整数.

如图，已知AB=DC，∠ABC=∠DCB，△ABC与△DCB全等吗？说明你的理由. A D-|||-3 C

2.int_(pi)^5pi(1+sin^3x)cos^2xdx=

2023年，第十三届全国大学生数学竞赛决赛试题（非数学类）二、(本题满分12分)求区间[0,1]上的连续函数f(x)，使之满足f(x)=1+(1-x)int_(0)^xyf(y)dy+xint_(x)^1(1-y)f(y)dy.

已知A=987654321×123456789,B=987654322×123456788.试比较A、B的大小.

若集合A=(x|x2-3x＜0)，B=(x|x2≥1)，则图中阴影部分表示的集合为（　　）A B A. (x|x＞0) B. (x|0＜x≤1) C. (x|1≤x＜3) D. (x|0＜x＜1或x≥3)

在下面这个序列中,下一个字母应该是什么?B A C B D C E D F

化简下列各个比．（1）0.05：1.5（2）10米：150厘米（2）2.2毫升：4升（4）114小时：45秒（5）335吨：1600千克．.

13.证明:若f(x)在[a,b]上连续,且 lt (x)_(1)lt (x)_(2)lt ... lt (x)_(n)lt b ,则在[x1,xn]上-|||-必有点ξ,使得 (xi )=dfrac (f({x)_(1))+f((x)_(2))+... +f((x)_(n))}(n) -

计算:-|||-1. (-2)+(-9)= __ _-|||-3. 5-(-2)= __-|||-5. -dfrac (7)(5)+dfrac (1)(10)= __ ---|||-7. (-53)+(+21)-(-69)-(+37)= __ _·-|||-8. (-dfrac (1)(6))+(+dfrac (1)(4))+(-dfrac (5)(6))+(-dfrac (3)(4))= __ _-|||-9. (-5dfrac (3)(4))-(-3dfrac (2)(3))-(-2dfrac (1)(3))-(+2.25)= __ _。-|||-10. (-14)-[ 6-(-12)] +(-9)= __ _.-|||-11. [ 1.4-(-3.6+5.2)-4.3] -(-1.5)=. __ --|||-12. -|-dfrac (3)(4)|-|dfrac (1)(5)-dfrac (1)(4)|-(-2)+dfrac (4)(5)= __ _.-|||-13. (-8)div (-1.25)= __ _·-|||-14. |1dfrac (1)(3)|div |-dfrac (5)(6)|= __ _.-|||-15. (-12)times (dfrac (1)(4)-dfrac (1)(3)-dfrac (1)(2))= __-|||-16. div dfrac (1)(7)times (-dfrac (4)(11))= __ _-|||-17. (-1.5)times dfrac (4)(5)div (-dfrac (2)(5))times dfrac (3)(4)= __ _-|||-18. (-18)div 2dfrac (1)(4)times dfrac (4)(9)div (-16)= __ _.-|||-19. div (-dfrac (1)(2)+dfrac (1)(3))= __ .-|||-20. (2dfrac (1)(3)-3dfrac (1)(2)+1dfrac (3)(4))div (-1dfrac (1)(6))= __ _-|||-21. div (-dfrac (1)(3)+dfrac (1)(4))times (-3)= __ _.-|||-22. ^3+(4)^2div (-2)= __ _.-|||-23. times (-dfrac (3)(4))-dfrac (3)(4)times (-4)-0.75times 11= __ _.-|||-24. -(3)^2+5times (-6)-((-4))^2div (-2)= __ --|||-25. div dfrac (1)(5)times (-dfrac (2)(13))+((-3))^2= __ _.-|||-26. -(6)^2div dfrac (3)(2)times dfrac (2)(3)+(0.5)^3= __-|||-27. -dfrac (1)(2)+dfrac (1)(2)div [ ((-1dfrac {1)(2))}^3+((-dfrac {1)(2))}^2] times ((-2.5))^2= __ --|||-2. (+18)+(-12)= __ _"-|||-4. -13-7+5= __ --|||-6. (3-7)-(-12-23)= __ .