更多“If w+x+y=42, what is the value of wxy?  (1) x and y are cons”相关问题
  • 第1题:

    1. public class X implements Runnable(  2. private int x;  3. private int y;  4.    5. public static void main(String[]args)  6. X that = new X();  7. (new Thread(that)).start();  8. (new Thread(that)).start();  9. )  10.    11. public void run()  (  12. for (;;)  (  13. x++; 14. y++;  15. System.out.printIn(“x=” + x + “, y = ” + y);  16.     ) 17. ) What is the result?()

    • A、 Errors at lines 7 and 8 cause compilation to fail.
    • B、 The program prints pairs of values for x and y that might not always be the same on the same line (for example, “x=2, y=1”).
    • C、 The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by “x=1, y=1”).
    • D、 The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears only for once (for example, “x=1, y=1” followed by “x=2, y=2”).

    正确答案:D

  • 第2题:

    过点(一1,0,1)且与平面X+Y+4z+19=0平行的平面方程为()。

    • A、X+Y+42-3=0
    • B、2x+Y+z-3=0
    • C、X+2y+z-19=0
    • D、X+2y+42-9=0

    正确答案:A

  • 第3题:

    单选题
    If x-y = 3 and x+y = 5, what is the value of y?
    A

    -4

    B

    -2

    C

    -1

    D

    1

    E

    2


    正确答案: C
    解析:
    Eliminate y by adding corresponding sides of the two equations: x-y=3, x+y=5, therefore 2x+0=8, so x=8/2=4. Since x= 4 and x -y = 3, then 4-y = 3, so y = 1.

  • 第4题:

    问答题
    What is the value of x-y?  (1) (x-y)2=25  (2) 4x=4 (y+3)

    正确答案: B
    解析:
    条件1不能确定x-y的值,由条件2可知,x-y=3,故本题选B项。

  • 第5题:

    单选题
    If 2x-3y = 11 and 3x+15 = 0, what is the value of y?
    A

    -7

    B

    -5

    C

    1/3

    D

    3

    E

    10


    正确答案: A
    解析:
    First solve the equation that contains one variable. Since 3x+15 = 0, then 3x = -15, so x = -15/3 = -5. Substituting -5 for x in the other equation, 2x-3y = 11, gives 2(-5)-3y = 11 or -10-3y = 11. Adding 10 to both sides of the equation makes -3y = 21, so y = -21/3 = -7.

  • 第6题:

    单选题
    If x is an integer and y=7x+11, what is the greatest value of x for which Y is less than 50?
    A

    7

    B

    6

    C

    5

    D

    4

    E

    3


    正确答案: A
    解析:
    解答这道题的快速方法是把选项中的数值依次代入方程式,计算y的数值,直到满足条件y<50为止,即可得出答案。

  • 第7题:

    单选题
    If (2y+ k) 2 =4y2-12y+ k2, what is the value of k?
    A

    3

    B

    1

    C

    -1

    D

    -2

    E

    -3


    正确答案: E
    解析:
    You are told that (2y + k) 2 = 4y2 - 12y + k2. Use the formula for expanding the square of a binomial:
    (2y + k) 2 = (2y) 2 + 2(2yk) + k2= 4y2 + 4yk + k2
    Compare 4y2 - 12y + k2 with 4y2 + 4yk + k2. Since the two trinomials must be the same, then -12y = 4yk, so k =-12y/4y =-3

  • 第8题:

    单选题
    If x-9 = 2y and x+3 = 5y, what is the value of x?
    A

    -2

    B

    4

    C

    11

    D

    15

    E

    17


    正确答案: C
    解析:
    Subtract corresponding sides of the two given equations: x+3=5y, x- 9= 2y →0+ 12=3y. 12/3 = y or y=4. Since y= 4 and x + 3 = 5y, then x + 3 = 5(4) = 20, so x=20-3=17.

  • 第9题:

    单选题
    If 3x+y = c and x+y = b, what is the value of x in terms of c and b?
    A

    (c-b)/3

    B

    (c-b)/2

    C

    (b -c)/3

    D

    (b-c)/2

    E

    (c-b)/4


    正确答案: B
    解析:
    Eliminate y by subtracting corresponding sides of the given equations: 3x+y=c, x+y=b. Therefore 2x+0=c-b, so x= (c-b)/2

  • 第10题:

    单选题
    What is the least possible value of (x+1)2 if -2≤x≤3?
    A

    -2

    B

    3

    C

    -1

    D

    0

    E

    1


    正确答案: E
    解析:
    Since (x+1) 2 is the square of a number, the least possible square of a real number must be 0.

  • 第11题:

    单选题
    public class X implements Runnable {  private int x;  private int y;  public static void main(String [] args) {  X that = new X();  (new Thread( that )).start();  (new Thread( that )).start();  }  public void run() {  for (;;) {  synchronized (this) {  x++;  y++;  }  System.out.println(Thread.currentThread().getName() +  “x = “ + x + “, y = “ + y);  }  }  }   What is the result?()
    A

     Compilation fails.

    B

     The program prints pairs of values for x and y that might not always be the same on the same line (for example, “x = 2, y = 1”).

    C

     The program prints pairs of values for x and y that are always the same on the same line (for example, “x = 1, y = 1”).    In addition, each value appears only once (for example, “x = 1, y = 1” followed by “x = 2, y = 2”).    The thread name at the start of the line shows that both threads are executing concurrently.

    D

     The program prints pairs of values for x and y that are always the same on the same line (for example, “x = 1, y = 1”).     In addition, each value appears only once (for example, “x = 1, y = 1” followed by “x = 2, y = 2”).    The thread name at the start of the line shows that only a single thread is actually executing.


    正确答案: B
    解析: 暂无解析

  • 第12题:

    填空题
    Let f(x) be defined as the absolute value of the difference between the smallest and largest odd factors of x greater than 1. For example, f(42)=︱3-21︱=18. What is the value of f(90)?____

    正确答案: 42
    解析:
    90最大的奇因数为45,最小的奇因子为3,所以f(90)=45-3=42。

  • 第13题:

    public class X implements Runnable (   private int x;   private int y;    public static void main(String args) (   X that = new X();   (new Thread(that)) . start( );   (new Thread(that)) . start( );   )    public synchronized void run( ) (    for (;;) (    x++;    y++;    System.out.printIn(“x = “ + x + “, y = “ + y);    )   )    )   What is the result?()

    • A、 An error at line 11 causes compilation to fail.
    • B、 Errors at lines 7 and 8 cause compilation to fail.
    • C、 The program prints pairs of values for x and y that might not always be the same on the same line  (for example, “x=2, y=1”)
    • D、 The program prints pairs of values for x and y that are always the same on the same line (forexample, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by  “x=1, y=1”)
    • E、 The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by  “x=2s, y=2”)

    正确答案:E

  • 第14题:

    int x = 1, y =6;  while (y--) {  x++;  }  System.out.println(“x =” + x + “y =” +y); What is the result?()  

    • A、 x = 6 y = 0
    • B、 x = 7 y = 0
    • C、 x = 6 y = -1
    • D、 x = 7 y = -1
    • E、 Compilation fails.

    正确答案:E

  • 第15题:

    单选题
    关系模式R(U,F),其中U=(W,X,Y,Z),F={WX→Y,W→X,X→Z,Y→W}。关系模式R的候选码是__(1)__,__(2)__是无损连接并保持函数依赖的分解。空白(2)处应选择()
    A

    ρ={R1(WY),R2(XZ)}

    B

    ρ={R1(WZ),R2(XY)}

    C

    ρ={R1(WXY),R2(XZ)}

    D

    ρ={R1(WX),R2(YZ)}


    正确答案: A
    解析: 暂无解析

  • 第16题:

    问答题
    If x+y=36, what is the value of xy?  (1) y-x=14  (2) y=2x+3

    正确答案: D
    解析:
    分别将两个条件代入题目,可以计算出x=11,y=25,故本题应选D项。

  • 第17题:

    填空题
    In the xy-plane, the graph of y = 2x2 + hx - 6 passes through the point (-3, -21), what is the value of h ?____

    正确答案: 11
    解析:
    因为(-3, -21)经过二次方程式,所以-21 = 2(-3)2 + h(-3) – 6,-21 = 18-3h-6= 12-3h,-33 =-3h,h = 11。

  • 第18题:

    单选题
    int x = 1, y =6;  while (y--) {  x++;  }  System.out.println(“x =” + x + “y =” +y); What is the result?()
    A

     x = 6 y = 0

    B

     x = 7 y = 0

    C

     x = 6 y = -1

    D

     x = 7 y = -1

    E

     Compilation fails.


    正确答案: B
    解析: A ‘while’ statement can only evaluate a Boolean expression. The expression while(y--) returns an int rather than a Boolean. Therefore, the correct answer is E. 

  • 第19题:

    问答题
    Is the value of x3y-x2y2+xy3 equal to 0?  (1) x=0  (2) y=0

    正确答案: D
    解析:
    由于每一项都包含x和y,故只要x、y有一个值为0,可知原式值为0,故本题选D项。

  • 第20题:

    单选题
    public class X implements Runnable(    private int x;   private int y;   public static void main(Stringargs)  X that = new X();   (new Thread(that)).start();  (new Thread(that)).start();  )  public void run() (  for (;;) (  x++;   y++;   System.out.printIn(“x=” + x + “, y = ” + y);   )   )   What is the result?()
    A

     Errors at lines 7 and 8 cause compilation to fail.

    B

     The program prints pairs of values for x and y that might not always be the same on the same line  (for example, “x=2, y=1”).

    C

     The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by  “x=1, y=1”).

    D

     The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears only for once (for example, “x=1, y=1”  followed by “x=2, y=2”).


    正确答案: A
    解析: 暂无解析

  • 第21题:

    单选题
    public class X implements Runnable (   private int x;   private int y;    public static void main(String args) (   X that = new X();   (new Thread(that)) . start( );   (new Thread(that)) . start( );   )    public synchronized void run( ) (    for (;;) (    x++;    y++;    System.out.printIn(“x = “ + x + “, y = “ + y);    )   )    )   What is the result?()
    A

     An error at line 11 causes compilation to fail.

    B

     Errors at lines 7 and 8 cause compilation to fail.

    C

     The program prints pairs of values for x and y that might not always be the same on the same line  (for example, “x=2, y=1”)

    D

     The program prints pairs of values for x and y that are always the same on the same line (forexample, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by  “x=1, y=1”)

    E

     The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by  “x=2s, y=2”)


    正确答案: A
    解析: 暂无解析

  • 第22题:

    单选题
    1. public class X implements Runnable(  2. private int x;  3. private int y;  4.    5. public static void main(String[]args)  6. X that = new X();  7. (new Thread(that)).start();  8. (new Thread(that)).start();  9. )  10.    11. public void run()  (  12. for (;;)  (  13. x++; 14. y++;  15. System.out.printIn(“x=” + x + “, y = ” + y);  16.     ) 17. ) What is the result?()
    A

     Errors at lines 7 and 8 cause compilation to fail.

    B

     The program prints pairs of values for x and y that might not always be the same on the same line (for example, “x=2, y=1”).

    C

     The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by “x=1, y=1”).

    D

     The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears only for once (for example, “x=1, y=1” followed by “x=2, y=2”).


    正确答案: A
    解析: 暂无解析

  • 第23题:

    问答题
    What is the value of y?  (1) y2+8y+16=0  (2) y<0

    正确答案: A
    解析:
    由y2+8y+16=0,可知y=-4;由条件2无法判断y的值,故本题选A项。