#include
void main0
int x=5;
switch(2*x-3) {
case 4: printf("%d "x);
case 7: printf("%d ",2*x+1);
case 10: printf("%d ",3*x-1); break;
default: printf("%s"," default/n");
}
}
____________________
A.若3x-1=2x+1,则3x+2x=1+1
B.若3(x+1)-5(1-x)=0,则3x+3-5-5x=0
C.若1-(3x-1)/2=x,则2-3x-1=x
D.若(x+1)/0.2-x/0.3=10,则(x+1)/2-x/3=1
方程|x+1|+|x+3|+|x-5|=9存在唯一解. (1)|x-2|≤3. (2)|x-2|≥2.
A.条件(1)充分,但条件(2)不充分.
B.条件(2)充分,但条件(1)不充分.
C.条件(1)和条件(2)单独都不充分,但条件(1)和条件(2)联合起来充分.
D.条件(1)充分,条件(2)也充分.
E.条件(1)和条件(2)单独都不充分,条件(1)和条件(2)联合起来也不充分.
试在数轴上表示出下列不等式的解:
(1)X(X2-1)>0; (2)|X-1|<|X-3|
(3)