24.证明: (int )_(0)^1dx(int )_(0)^xf(x-y)dy=(int )_(0)^1f(x)(1-x)dx-|||-"f(x-y)dy=∫0,f(x)(1-x)d

设 iint_(D) f(x, y)dx dy = int_(0)^1 dx int_(0)^1-x f(x, y)dy，则改变其积分次序后为A. $\int_

计算(int )_(0)^1dx(int )_(1-x)^sqrt (1-{x^2)}dfrac (x+y)({x)^2+(y)^2}dy=-|||-dv=__

(int )_(0)^1dx(int )_(x)^1(e)^-(y^2)dy= () .-|||-

(B) (int )_(-1)^1f(x)dxlt 0.-|||-(C) (int )_(-1)^0f(x)dxgt (int )_(0)^1f(x)dx. (

(B) (int )_(-1)^1f(x)dxlt 0.-|||-(C) (int )_(-1)^0f(x)dxgt (int )_(0)^1f(x)dx. (

（请画图➕解答过程）3.交换积分次序:-|||-(1) (int )_(0)^1dx(int )_(x)^sqrt (x)f(x,y)dy;（请画图➕解答过程）

设(x)=dfrac (1)(1+{x)^2}+sqrt (1-{x)^2}(int )_(0)^1f(x)dx, 则 (int )_(0)^1f(x)dx=设

设 iint_(D) f(x, y), dx , dy = int_(0)^1 dx int_(x)^2x f(x, y), dy，其中 f(x, y) 是连续

若 int f(x)dx = sin x + C，则 int xf(1-x^2)dx = ( )A. $2\sin(1-x^2)+ C$B. $-\frac{1

设 f ( x ) 是连续奇函数且(int )_(0)^1f(x)dx=-2 则 (int )_(0)^1f(x)dx=-2设f(x)是连续奇函数且则