There are four propositions in the definition of positive logarithm: if a > 0, b > 0, then ln + (AB)

There are four propositions in the definition of positive logarithm: if a > 0, b > 0, then ln + (AB)

Hope it works for you

What is the meaning of logarithm of function?

It is the expression of a function, which is regarded as an equation, and the left and right sides take logarithm at the same time
[example] for the power function y = x ^ 2, take the common logarithm on both sides at the same time to get lgY = 2lgx
At the same time, LNY = 2lnx is obtained by taking the natural logarithm

What is the difference between the common logarithm and the natural logarithm? Is it just for the convenience of calculation to take logarithm for the ghost function? Is there any change in the meaning of the function?

The commonly used logarithm is based on 10, written as log 10 X
The natural logarithm is based on e, e = 2.7182818..., written as: ln x, base e omitted
Sometimes it is convenient to take logarithm for the function y = x ^ A, and the meaning of the function does not change

1. Xiao Wang said to Xiao Li: "you think of a number, multiply by 4, add 20, then divide by 2, its quotient minus 8, then divide by 2, finally subtract the number you think, I will know the result." can you know?
2. A passenger car is moving at the speed of 80km / h, and a freight car is oncoming. The time for passing by the passenger car is 3 seconds. The length of the freight car is known to be 150m, so the speed of the freight car can be calculated
3. Given | x + 3 | + | 2y-3 | = 0, find the value of X + y
4. Find the minimum value of | X-1 | + | X-2 |
5. Find the value of a + | B + | C | C of the algebraic formula | a | min

1. According to Xiao Wang
{(4X+20)/2-8}/2-X=?
It is simplified to x + 5-4-x = 1
So whatever number you think, it turns out to be 1
2. Change the unit first
When 3S = 1 / 1200, 150m = 0.15km
Let the speed of freight car be x (km / h)
Then (80 + x) / 1200 = 0.15
X = 100
The speed of the truck is 100 km / h
3. From | x + 3 | + | 2y-3 | = 0
We get x + 3 = 0, 2y-3 = 0, x = - 3, y = 3 / 2
So x + y = - 3 + 3 / 2 = - 3 / 2
4.|x-1|+|x-2|≥0
When | X-1 | = 0, | X-2 | = 1
When | X-2 | = 0, | X-1 | = 1
When 1 ≤ x ≤ 2, there is a minimum value of 1
five

If the natural numbers are arranged according to the following rules, the position of 2008 is the third______ Line number______ First column second column third column fourth column First line 1 2 9 10 The second line 4 3 8 11 The third line 5 6 7 12 The fourth line 16 15 14 13 Line five 17     … …          

2008 = 442 + 72, 442 = 1936, then the number starts from the 45th row in 1937, turns from the 45th column in 1981, and the position of 2008 is the 18th row and the 45th column in the 18th row

The product of all integers with absolute values greater than 3.7 and not greater than 6 is

4×5×6×﹙－4﹚×﹙－5﹚×﹙－6﹚=－14400

English Chinese translation,
Jackie Chan is famous as an action actor
Jackie Chan is___ ___ an action actor.
I want to do something different this time
___ ___ I want to do something different.
I forgot that I had told Jim about it
I forget___ Jim___ it.
We decided to go to Beijing for our holiday
we___ ___ apend our vacation in Beijing.
I think about having a class meeting
I`m___ ___ having a class meeting.

1.famous for
2.This time
3.tell about
4.decide to
5.thinking about

There are 160 red, yellow and white balls. If you take out 13 red balls, 14 yellow balls and 15 white balls, there are 120 left. If you take out 15 red balls, 14 yellow balls and 13 white balls, there are 116 left. How many red, yellow and white balls are there?

According to the above analysis, taking 160 △ 40 = 4 times just finished, red ball is still poor: 43-1 = 13, white ball is more than 1-45 = 15, yellow ball is finished; it shows that 13 of red ball is equal to 15 of white ball, the ratio of red ball to white ball is 3:5; according to the comparison of two schemes, it is found that 13-15 = 215 of white ball is more than 215 of red ball by 4; that is, white ball is more than red ball by 4 △ 215 = 30, so red ball has 30 △ 215（ 5-3) × 3 = 45; white ball has 45 + 30 = 75; yellow ball is 160-45-75 = 40; answer: (1) original yellow ball 40, (2) original red ball 45, white ball 75

How many meters per second is 90 meters per minute

1 minute = 60 seconds
90 △ 60 = 1.5 meters per second

*Divided by a equals 4 4. Add a post if you answer right
*Divide B by 5 5. There must be a process,
*Divided by C equals 6 six
What are *, a, B and C?

*It can be divisible by 4,5,6 at the same time
The least common multiple of 4,5,6 is 60
*：60
60-4=56
a:56÷4=14
60-5=55
b:55÷5=11
60-6=54
c:54÷6=9