(1) 2, - 4,8,11 use these four numbers to do a 24 point game (2) and the other four numbers 3, - 7,8,13 can be made equal to 24 by ()

(1) 2, - 4,8,11 use these four numbers to do a 24 point game (2) and the other four numbers 3, - 7,8,13 can be made equal to 24 by ()

(1) 2 × (-4) × ( 8-11)
2 - 8 × 11 ÷(- 4)
(2) Another four numbers 3, - 7,8,13 can be made equal to 24 by (3 × 13 + (- 7) - 8)
"24" point game, with 2, 6, 9, 9 together into 24 points (each number only once), the formula is______ .
From the meaning of the question, we can see that: ∵ 242 = 12, 9 + 9-6 = 12, ∵ 24 = 2 × 12 = 2 × (9 + 9-6), so the formula is (9 + 9-6) × 2
If the four numbers are 2, 6, 9 and 9, the formula is
1: (2 + 6 ÷ 9) × 9
2: (2 + (6 ÷ 9)) × 9
3: 2 × (9 - 6 + 9)
4: 2 × ((9 - 6) + 9)
5: 2 × (9 - (6 - 9))
6: 2 × (9 + 9 - 6)
7: 2 × ((9 + 9) - 6)
8: 2 × (9 + (9 - 6))
9: (6 ÷ 9 + 2) × 9
10: ((6 ÷ 9) + 2) × 9
11: 9 × (2 + 6 ÷ 9)
12: 9 × (2 + (6 ÷ 9))
13: (9 - 6 + 9) × 2
14: ((9 - 6) + 9) × 2
15: (9 - (6 - 9)) × 2
16: 9 × (6 ÷ 9 + 2)
17: 9 × ((6 ÷ 9) + 2)
18: (9 + 9 - 6) × 2
19: ((9 + 9) - 6) × 2
20: (9 + (9 - 6)) × 2
Given that the function f (x) = loga (3x2-2ax) is a decreasing function in the interval [1 / 2,1], find the value range of real number a
If the function is meaningful, 0
In the international system of units, thermodynamic temperature is used___ The unit name of temperature is____ Abbreviation_____ The symbol is___ ?
Absolute zero Kelvin K
-273.15 degrees, Kelvin, Kelvin, K
The international system of units adopts thermodynamic temperature, which is the temperature starting from absolute zero. The unit name of temperature is Kelvin, abbreviated as Kai, and the symbol is K
In the international system of units, thermodynamic temperature is adopted, which starts from (- 273.15 ℃). The unit name of temperature is (Kelvin "Kelvin") and the symbol is (k)
50 mixed operations of addition, subtraction, multiplication and division of rational numbers in the first year of junior high school
Rational mixing operation 1 (- 9) - (- 13) + (- 20) + (- 2) (2) 3 + 13 - (- 7) / 6 (3) (- 2) - 8-14-13 (4) (- 7) * (- 1) / 7 + 8 (5) (- 11) * 4 - (- 18) / 18 (6) 4 + (- 11) - 1 / (- 3) (7) (- 17) - 6-16 / (- 18) (8) 5 / 7 + (- 1) - (- 8) (9) (- 1) * (- 1) + 15 + 1 (10) 3 - (- 5) * 3 / (- 15) (1
The function f (x) = loga (AX ^ 2-x) is a decreasing function on [2,4], and the value range of the real number a is obtained
When a > 1, f (x) = ax ^ 2-x = a (x-1 / (2a)) ^ 2-1 / (4a), the opening is upward, the symmetry axis is x = 1 / (2a) on the left side of the interval, so f (x) increases in the interval, and f (x) also increases. If f (2) = 4a-2 > 4-2 > 0, a > 1 satisfies the condition
When 0 A0 --- > a > 1 / 4, it does not meet the requirement
The range of a is a > 1
00
loga^[(2a-1)/(4a-1)]-loga^2>0
Log a ^ [(2a-1) / (4a-1) > log a
∵ f (x) is a decreasing function on [2,4]
That is, f (2) - f (4) > 0
loga^(4a-2)-loga^(16a-4)>0
loga^[2(2a-1)/4(4a-1)>0
loga^{(1/2)[(2a-1)/(4a-1)}>0
loga^[(2a-1)/(4a-1)]-loga^2>0
loga^[(2a-1)/(4a-1)>loga^2
(2a-1)/(4a-1)>2
When a > 1 / 4, 2a-1 > 2 (4a-1)
Solution: A1 / 4, rounding off)
When a
In daily life, the unit of electric energy is symbol. In the international system of units, the unit of energy is symbol for short?
Watt, symbol W. international. Joule, short for Joule, symbol J
The mixed operation of addition, subtraction, multiplication and division of rational numbers
Just remember the operation order
First calculate the power, then multiply and divide, and finally add and subtract
If there are brackets, calculate the brackets first, multiply and divide them together in order
Given that the function f (x) = 2 (A-1) x + 2 is a decreasing function in the interval (- ∞, 4), how to find the value range of real number a?
F (x) = 2 (A-1) x + 2 is a decreasing function in the interval (- ∞, 4)
SO 2 (A-1)