【单选题】
设有向图D = áV, E?, 其中 V={v1, v2, v3, v4, v5}, E={áv4, v1?, áv1, v1?,áv1, v2?,áv1, v3?, áv3, v1?, áv5, v3?},则v1的闭邻域 N(v1) =
【单选题】
反应2NaHCO3(s)=Na2CO3(s)+H2O(g)+CO2(g)在温度T时的标准平衡常数为90,该反应的压力平衡常数是()
【简答题】
统计整数n的各个位上出现数字1、2、3的次数,并通过外部(全局)变量c1、c2、c3返回主函数。
例如,当n=123114350时,结果应该为:c1=3 c2=1 c3=2。
#includeint c1,c2,c3;
void fun(long n)
{
c1 = c2 = c3 = 0;
while (n)
{
/************found************/
switch([填空1])
{
case 1: c1++; break;
/************found************/
case 2: c2++;[填空2]
case 3: c3++;
}
n /= 10;
}
}
main()
{
int n=123114350;
fun(n);
printf(\nn=%d c1=%d c2=%d c3=%d\n,n,c1,c2,c3); }
【单选题】
minZ=4x1+6x2,4x1+3x2≤24,x2≥9,x1,x2≥0,则()。
【简答题】
设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R2={|x, y∈Xùy-1y+2},则R2(-1) =[填空1]
【单选题】
已知电对I2/I-和MnO4-/Mn2+在25℃时的标准电极电势分别为0.54V和1.51V,若将其构成原电池的总反应式如下:2 MnO4- + 16H+ + 10I- <img class="kfformula" src="data:image/png;base64,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" data-latex="\leftrightharpoons "/>2 Mn2+ + 8H2O + 5I2, 则该原电池的<img class="kfformula" src="data:image/png;base64,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" data-latex="{E}^{\theta }"/>等于 ( )
【单选题】
a=(1,2,3);语句执行后,a的值是()
【单选题】
设 A = {1, 22, 43, 3},B = {1, 32, 44, 2},则差关系A-B的域fld(A-B)等于:
【单选题】
设 A = {1, 22, 43, 3},B = {1, 32, 44, 2},则交关系A∩B的值域ran(A∩B)等于:
【单选题】
已知向量组a1,a2,a3,a4线性无关,则向量组( )
①
a1+a2,a2+a3,a3+a4,a4+a1线性无关
②
a1-a2,a2-a3,a3-a4,a4-a1线性无关
③
a1+a2,a2+a3,a3+a4,a4-a1线性无关
④
a1+a2,a2+a3,a3-a4,a4-a1线性无关