P=2^100-2^99-2^98-......-2^2-2-1. ĐỀ BÀI LÀ TÍNH NHANH CÁC BN Ạ. CÁC BN KP VS MK NHA
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Những câu hỏi liên quan
HP
27 tháng 1 2016
A=2^100-2^99+2^98-2^97+..+2^2-2
=>2A=2^101-2^100+2^99-2^98+...+2^3-2^2
=>2A+A=(2^101-2^100+2^99-2^98+..+2^3-2^2)+(2^100-2^99+2^98-2^97+..+2^2-2)
=>3A=2^101-2
=>A=(2^101-2)/3
Q
27 tháng 4 2020
Trả lời:
Ta có : 1.22= 1.2.2=1.2.(3-1)=1.2.3-1.2
2.32= 2.3.3=2.3.(4-1)=2.3.4-2.3
.................................................
98.992= 98.99.99=98.99.(100-1)=98.99.100-98.99
A=1.2.3 - 1.2 + 2.3.4 - 2.3 + ... + 98.99.100 - 98.99 hay A=1.2.3 + 2.3.4 +...+ 98.99.100 - (1.2 + 2.3 + ... + 98.99) = B - C
B=1.2.3 + 2.3.4 + ... + 98.99.100
B.4=1.2.3.4 + 2.3.4.(5 - 1) + ... + 98.99.100.(101 - 97)= 98.99.100.101
=> 98.99.100.101:4= 24497550
C=1.2 + 2.3 + ... + 98.99
C.3=1.2.3 + 2.3.(4 - 1) + ... + 98.99.(100 - 97)= 98.99.100
=> 98.99.100:3= 323400
Vậy A= 24497550 - 323400 = 24174150
18 tháng 2 2016
1 + ( 2 - 3 - 4 + 5 ) + (6 - 7 - 8 + 9 ) +....+ ( 98 - 99 -100 ) 1 + 0 + 0 +...+ (-101) 1 + (-101) = 100 đúng 100 phần trăm luôn
18 tháng 2 2016
tính tổng
1 + 2 - 3 + 4 ... + 97 + 98 - 99 - 100
nhanh lên nhé, mik cần gấp. ah mà các bn giải cụ thể giùm mik nha
Toán lớp 6
HH
18 tháng 1 2018
Đề 1 : Talk about your bestfriend
Hello everybody,my name is Vy.If you want me to tell you about one of my friends,I will think about my best friend firstly.
Her name is Duyen.If you ask : "How does she look ".I will answer : She is tall but slim,she has an oval face with straight nose,big eye, warm slime, and long black hair.I think a Vietnamese girl her is very beautiful.And what about her personality ? She is friendly,careful,kind,.....all good personality that one can have.Not only that, she is a very kind person. Always open your heart to everyone, share, encourage when you are sad, encourage you to do something you want or even happier than you when you get good things.Duyen want to be a teacher, her mother so she studies very hard and always gets good marks but she never arrogant.Duyen is also a funny girl,she always makes me laugh so much when we meet each other.We always play,study and many many activities together.
Maybe later we will not learn or even meet again but I still want to keep the memories of this beautiful friendship in the heart, forever ...
Finally,I want to say to every body : "“Best friends are the people in your life that make you laugh louder, smile brighter and live better”
---------------------------------------------------------Let the sweet friendship refresh your soul----------------------------------------------------------------
17 tháng 1 2018
đề 1:I have many friends, but i want to tell you about my best friend. Her name is....She is tall and cute. She has dark hair and a round face. We first met each other when we entered primary school. She was my classmate and her seat next to me. We both cooking and reading magazines....We also studying maths and english. But she is a bit better at maths than me. Therefore, she often helps me do maths homework. I really her and I hope to be her best friend forever.
đề 2:............ is the name of my school. It is not very large but it is very beautiful. There are a lot of grean trees along the schoolyard. It has 3 floors. The classroom is full of desks and chair, there is also a blackboard and 8 fans. The teachers are thoughtful and friendly. They always take care of us, so I love them. I have many friènd there. I love my school so much
Cs j sai thì tc cho mik nhoa <3
TL
1
10 tháng 10 2015
Ta co :
1/2! +2/3! +3/4! +... + 99/100!
= (1/1! -1/2!) + (1/2! - 1/3!) + (1/3! -1/4!) + .... + (1/99! -1/100!)
=1 - 1/100! <1
lik e nhe
ZK
0
12 tháng 1 2017
mình chỉ biết câu b thôi
b , 1+2-3-4+5+6-7-8+.......+97+98-99-100+101
=1+(2-3-4+5)+(6-7-8+9)+......+(98-99-100+101)
=1+0+0+.....+0
=1
bạn nè có viết thiếu đề ko rứa nếu mình sửa lại đề thi bài mình làm đúng rồi đó
18 tháng 3 2018
b)1+2-3-4+5+6-7-8+.....+97+98-99-100
=(1+2-3-4)+(5+6-7-8)+...+(97+98-99-100)
=-4+(-4)+...+(-4)
mà biểu thức có 25 nhóm
=>biểu thức=25(-4)=-100
<=> P = 2100 - ( 299 + 298 + ..... + 22 + 2 + 1 )
Đặt A = 1 + 2 + 22 + 23 + ...... + 298 + 299
<=> 2A = 2.( 1 + 2 + 22 + ..... + 298 + 299 )
<=> 2A = 2 + 22 + 23 + ...... + 299 + 2100
<=> 2A - A = ( 2 + 22 + 23 + ..... + 299 + 2100 ) - ( 1 + 2 + 22 + ..... + 298 + 299 )
<=> A = 2100 - 1
=> P = 2100 - ( 2100 - 1 )
=> P = - 1
Vậy P = - 1