Given the function f (x) = log2 (x + A / x) (a is a constant), if the function is an increasing function at (2, positive infinity), find the value of A

1) When a = 1, f (x) = log2 (x + 1 / x), then if the minimum log2 is X. > 0 is an increasing function, we can get the minimum value of X + 1 / X. using the result of mean inequality > = 2, then f (x) = log2 ^ 2 = 1 is the minimum value
2) If x > 0, then f (x) = log2 (x + A / x) (a is a constant) and G (x) is an odd function, and if x > 0, G (x) = f (x), then f (- x) = - f (x) is also an odd function

The known function f (x) = log2 (x-a) [A is a constant]
(1) If f (2) = 2, find the value of A
(2) If f (x) is significant on (1, positive infinity), find the value range of A

f(2)=log2(2-a)=2
2-a=4
a=-2
(2) The domain of definition is x-a > 0, that is x > a
If the function is meaningful in (1, + infinity), then there is a

It is known that the function f (x) defined on R satisfies f (log2, x) = x = A / x, and a is a constant
The analytic expression and definition field of function f (x)
Wrong number. The second equal sign is the plus sign

Let log2x = t
Then x = 2 ^ t
f(t)=x+a/x=2^t+a/2^t
f(x)=2^x+a/2^x
Next time you encounter the same problem, make the formula in brackets equal to t, then find the analytic formula of X about t, bring in the original formula, and then convert t into X

The function y = f (x) is undefined at x0, which is the condition that it has no limit at x0
Whether it is sufficient or necessary depends on the condition

Necessary!

Calculate with calculator: ① √ 7-off =? (accurate to 0.001) ② √ 3 × & # 179; √ 3 =? (accurate to 0.01)

Is √ 7 - not = - 0.496 √ 3 × & # 179; √ 3 = 15.588 correct

Use a calculator to find the values of the following formulas (accurate to 0.0001) (1) 0.3 ^ (2) 5 / 4 to the power of - 4 (3) 1g 7 (4) 1n 4.75（

1)0.4856 2)0.4096 3)0.8451 4)1.5581

Is 1 / 3 on arcsin 1 / 3 calculator 1 / 3 or 3 / 3

It's one in three
Enter 1, \, 3 respectively

1. Calculate {accurate to 0.01}: sin20; cos70 °; sin35 °; cos55 °; sin15 ° 32'cos74 ° 28 '
What conjecture do you have and test it

Sin20 = 0.34, cos70 ° = 0.34, sin35 = 0.57, cos55 ° = 0.57, sin15 ° 32 '= 0.27; cos74 ° 28' = 0.27 (all about equal to ah)
The conclusion is that if two angles complement each other, the sine value of one angle is equal to the cosine value of the other
Verify that (it's better to draw a picture) in the right triangle ABC, the two acute angles (∠ a, ∠ b) complement each other, the opposite side of a is a, the opposite side of B is B, and the opposite side of C is C
Sin a = A / C (a to c), cos B = A / C
So Sina = CoSb
Above, this is how I write this question. It's all my own groping Should be right. I hope I can help you

Keep three decimal places by computer calculation
The square root 1000 is approximately equal to
The quintic root - 640 is approximately equal to
-The sixth root 518 is approximately equal to
The quintic root - 2 and 3 / 5 is approximately equal to
The root of 10 times 0.3 is approximately equal to

5.623
-3.641
-2.834
-1.211
zero point eight eight seven
Computer calculation

What is the most basic working principle of computer?
I want to know how the computer does the calculation. I know that all operations can be converted into four arithmetic operations, and four arithmetic operations can be converted into addition operations. But how does the addition operation work? For example, how do I get 8 when I hit a "3 + 5" computer? What are the most basic physical changes in the computer? I hope you can use the simplest reason to say it

I can't say it in the simplest way. I'll use the following description to see if you can understand it
1) The most basic structure of computer: keyboard + CPU +)+
2) CPU is the center of external processing. It is a complex electronic circuit. This circuit has its own logic functions (such as addition, subtraction, multiplication, operation and other operations). It receives electrical signals
2-2). The operation of CPU is to calculate the received electrical signal. If you want to calculate, you have to convert 3, 5 + into electrical signal and send it
3) The keyboard converts the number you press into an electrical signal and sends it to the CPU
4) Memory is used to store the number (electrical signal) you input and the result it calculates, which is also the electrical signal
5) Display is to display the result (electrical signal) calculated by CPU to you in the form of light. Of course, it will convert the result into the digital shape we know
So, how does the 3 + 5 "computer get 8? The 3, +, 5 and so on are converted into electrical signals and sent to the CPU. According to its logic operation, the CPU adds the electrical signals of 3 and 5 to get the electrical signals of 8, which are stored in the memory, and then displayed in the corresponding digital shape through the display
The details will be more complicated

Given the function f (x) = log2 (x + A / x) (a is a constant), if the function is an increasing function at (2, positive infinity), find the value of A