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Xiao Gang and Xiao Ming donated 28 books in total. Xiao Gang donated 6 more than Xiao Ming. How many books did Xiao Gang and Xiao Ming donate to solve the equation
If Xiao Ming donated x books, then Xiao Gang donated x + 6 books
X+X+6=28
2X=22
X=11
11+6=17
Xiao Gang donated 17 and Xiao Ming donated 11
Xiaogang and Xiaoqiang want to buy the same magazine. Xiaoqiang's one book is 1.1 yuan less than Xiaogang's, and Xiaogang's one book is 1.2 yuan less than Xiaoqiang's. If they buy one book together, the rest is 0.7 yuan
A magazine costs () yuan
Magazine = 1.1 + 1.2-0.7 = 1.6 yuan
A natural number n ()
A. There is a minimum of 63b. There is a maximum of 63c. There is a minimum of 31d. There is a maximum of 31
Let the sum of the first n terms of {an} be Sn = log223 + log234 + +log2nn+1+log2n+1n+2，=[log22-log23]+[log23-log24]+… +[log2n-log2 (n + 1)] + [log2 (n + 1) - log2 (n + 2)] = [log22-log2 (n + 2)] = log22n + 2 ＜ - 5, that is, the solution of 2n + 2 ＜ 2-5 leads to N + 2 ＞ 64, n ＞ 62; the minimum value of natural number n that makes Sn ＜ - 5 hold is 63
Sqrt (1 + X * x) indefinite integral
Let x = tant DX = sec ^ 2tdt
∫√(1+x^2)dx
=∫sec^3tdt
=∫(sin^2t+cos^2t)/cos^3tdt
=∫dt/cost+∫sin^2t/cos^3tdt
=∫sectdt-∫sint/cos^3td(cost)
=∫sectdt-1/2*∫sintd(1/cos^2t)
=∫sectdt-1/2*sint/cos^2t-1/2*∫dt/cost
=1/2*ln|sect+tant|-1/2*sint/cos^2t+C
=x/2*√(1+x^2)+1/2*ln|x+√(1+x^2)|+C
Find the rule 1.4.9.16 () ()
25
In a of 8 (a equals a natural number), when a () it is a true fraction, when a () it is a false fraction, and when a equals () it is 0
When a is less than 8, it is a true fraction. When a is greater than or equal to 8, it is a false fraction. When a = 0, it is 0. I hope it can help you
Natural numbers are part of integers______ (judge right or wrong)
It is correct that the natural number used to represent the number of objects is part of an integer
1,2,10,11,12,20,21,22 (), ()
30,31
Find a natural number, it can be divided by 2 and 49, a total of 10 divisors
In general, let n be decomposed into n = P (1) ^ α (1) · P (2) ^ α * 2 · ·P (k) ^ α (k) where p 1, P 2 P (k) is a different prime number, α (1), α (2) If α (k) is a positive integer, then n = P (1) ^ β (1) · P (2) ^ β * 2 · ·p(k)^...
If the image of exponential function f (x) is known to pass through point (4,2), then f (x) =? F (x) =?
Exponential function f (x)
Let f (x) = a ^ X
Image over (4,2)
∴ a^4=2
∴ a=2^(1/4)
∴ f(x)=[2^(1/4)]^x
RELATED INFORMATIONS
- 1. Xiao Gang read a story book. He planned to read 39 pages a day and finish it in 30 days. Actually, he finished the book in 26 days. How many pages a day on average?
- 2. The average weight of Xiaoming and Xiaoliang is 41.5kg. The average weight of Xiaoliang and Xiaoqiang is 46kg. The average weight of Xiaoming and Xiaoqiang is 45.5kg. What's the weight of Xiaoming, Xiaoliang and Xiaoqiang? Formula
- 3. Xiao Ming and Xiao Gang collected 121 cards. It is known that one fifth of the number of Xiao Ming's cards is equal to one sixth of the number of Xiao Gang's cards. How many cards do Xiao Ming and Xiao Gang collect? Find the formula and explain
- 4. Xiaogang is 1 / 5 heavier than Xiaohua. Xiaohua's weight is 35 kg. Xiaoming is 1 / 7 lighter than Xiaohua. How many kg do they use the equation to solve
- 5. Xiaohua weighs 35 kg. Xiaogang weighs 1 / 5 more than Xiaohua. What's Xiaogang's weight
- 6. It costs 1 / 3 of the total money to use a pen and 4 yuan to buy a story book. At this time, the ratio of the money spent to the rest is 5:4. What is the original money? How to write this question?
- 7. Xiaohua weighs 35 kg, which is 5 / 7 of Xiaogang's weight. How many kg does Xiaogang weigh A ballpoint pen costs 3 / 2 yuan, which is exactly 1 / 8 of a pen. How much is a pen
- 8. Xiao Ming, Xiao Liang and Xiao Gang have played table tennis. Xiao Ming has played five games, Xiao Liang has played four games and Xiao Gang has played three games. How many games have these three children played in total? The specific calculation method is needed It's right to say this, say that, and say that
- 9. Xiaogang is 3.64kg heavier than Xiaoming, and Xiaoli is 2.8kg lighter than Xiaoming. Who is heavier, Xiaogang and Xiaoli? How many kg? There should be steps,
- 10. Xiao Gang has read a 250 page story book for five days, with an average of 26 pages a day, and the rest 30 pages a day. How many days will it take to finish?
- 11. Xiao Ming and Xiao Gang are about 1.7 * 10 & sup2; in height, but is Xiao Ming right when he says, "Xiao Gang is 9cm shorter than me"
- 12. How many years later, mother's age is three times the age of Xiaoqiang?
- 13. Mingming is 12 years old and Qiangqiang is 7 years old. When the sum of their ages is 45, how old are they?
- 14. Wei Wei is 8 years old and his father is 34 years old______ My father is three times as old as Wei Wei
- 15. My father is four times older than Xiaogang this year. Five years later, my father is 24 years older than Xiaogang. How old is Xiaogang five years later?
- 16. My grandfather is 84 years old, which is three times of my father's age. My father's age is seven times of Xiaogang's age
- 17. Xiaoying is three years younger than Xiaoming. This year, their age is half the age of the teacher. In another 15 years, their age is equal to the age of the teacher. This year, Xiaoying is a teacher______ I'm 40 years old
- 18. Xiaoming, Xiaogang and Xiaohong cut a total of 360 kg of grass. Xiaoming cut half of the other two and Xiaogang cut one third of the other two Xiao Ming, Xiao Gang and Xiao Hong cut a total of 360 kg of grass. Xiao Ming cut half of the other two, and Xiao Gang cut one third of the other two. How much grass did each of the three cut? What we want today! It's a formula
- 19. Xiao Ding, Xiao Wang three good friends, the age is just three consecutive natural numbers. And their three years multiplied by 504. How old are they?
- 20. Qiang Qiang, Wei Wei and Liang Liang are three good friends. Their age is three consecutive natural numbers. The product of the three numbers is 504. Guess how old are they?