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A. If B, C and D are four points in order on a straight line, and AC = 10, BD = 8, then the value of AB * CD + BC * ad is equal to____ .
AB*CD+BC*AD=AB*CD+BC(AB+BD)
=AB*CD+BC*AB+BC*BD
=AB(CD+BC)+BC*BD
=AB*DB+BC*BD
=BD(AB+BC)
=BD*AC=80
What is the sign of positive real numbers?
The R + plus sign is written at the top right of R
How is real number coding realized?
The computer stores the complement code, that is, the number is converted into binary code, the sign bit is positive for 0, negative for 1; then the binary code is inversed (except the sign bit, each 0 becomes 1, 1 becomes 0); and then the complement code of the original number is obtained by adding 1 to the inverse code. The computer stores the complement code. For real numbers, the scientific counting method is adopted
RELATED INFORMATIONS
- 1. We define the symbol | a B | C D |, which means | a B | C D | = ad BC We specify the symbol | a B| |c d|, It means | a B| |c d| = ad-bc , For example, 1 2| |3 4| =1*4-2*3=-2 If | x + 1 2x| |2 / 3, 1 / 2 | = 1, Find the value of X
- 2. Given that the real numbers a, B, C and D are not equal to each other, and a + 1b = B + 1C = C + 1D = D + 1A = x, try to find the value of X
- 3. Known x, y, Z are real numbers, if x + y + Z ≠ 0, a = x / x + y, B = Y / Z + X, C = Z / x + y, find the value of a / A + 1, B / B + 1, C / C + 1, please answer in detail!
- 4. a. B are different prime numbers, and 1 / A + B / a = 20 / 91, what are a and B?
- 5. 16 = () + () = () + () prime
- 6. The least common multiple of the three prime numbers is 42. The three prime numbers are (), (), ()
- 7. The least common multiple of the three prime numbers is 42, and the three prime numbers are (), () and (). There is a reward for it
- 8. The product of all prime numbers within 10 minus the largest two digits, the difference is______ ．
- 9. What's the difference between the product of prime numbers within 10 plus the smallest two digits and subtracting the smallest two digits and subtracting the smallest three digits
- 10. Given that AB is prime and 3a + 2B = 2000, find the value of a + B
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- 12. ABCD, the absolute value of ABCD is divided by ABCD to get negative 1. Find the absolute value of a in a + B in B + C in C + D in D
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- 14. The point representing an integer on the number axis is called integral point. The unit length of a certain number axis is 1cm. If a line segment AB with length of 2010cm is drawn randomly on the number axis, the integral point covered by the line segment AB is () A. 2009 B. 2010 C. 2010 or 2009 D. 2010 or 2011
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- 16. When a ship goes back and forth between a and B, assuming that the speed of the ship in still water does not change, the time it takes for the ship to go back and forth once when the water velocity increases______ (a) no change (b) increase (c) decrease (d) increase or decrease is possible
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