Rut gon bieu thuc :
E = 2100 - 299 + 298 - 297 + ... + 22 - 21
Giai gium minh nha cac ban con ai la Giao vien thi lam ho em a !
Rut gon bieu thuc :
D = 57 + 511 + 515 + ... + 54k+3
(K\(∈\)N , K > 2)
Nhanh nha moi nguoi 2 nhanh nhat minh tick cho con ai la giao vien tra loi gium em a !
\(D=5^7+5^{11}+5^{15}+...+5^{4k+3}\) (1)
Nhân D với 54 ta được:
\(5^4.D=5^{11}+5^{15}+...+5^{4k+7}\) (2)
Lấy (2) trừ đi (1) ta được:
\(5^4.D-D=5^{4k+7}-5^7\)
=> \(D=\frac{5^7\left(5^{4k}-1\right)}{5^4-1}\)
Rut gon bieu thuc :
D = 57 + 511 + 515 + ... + 54k+3
(K\(\in\)N , K > 2)
Nhanh nha moi nguoi 2 nhanh nhat minh tick cho con ai la giao vien tra loi gium em a !
cac ban oi giup minh cau nay vs
rut gon cac bieu thuc sau
3x^2 - 2x . (5+1,5x) + 10
giai giup mik vs
\(3x^2-2x.\left(5+1,5x\right)+10\)
\(=3x^2-2x.5-2x.1,5x+10\)
\(=3x^2-3x^2-10x+10\)
\(=10-10x\)
\(=10.\left(1-x\right)\)
1.Rut gon cac phan so sau: 15/24 ; 21/42 ; 54/18 ; 100/25 . (day la toan lop 4 cac ban a, lam nhanh cho minh cac ban nhe)
15/24 = 5/8 ; 21/24 = 7/8 ; 54/18 = 9/3 ; 100/25 = 4/1.
15/24=5/8;21/42=1/2;54/18=3/1;100/25=4/1
15/24 = 5/8
21/42 = 7/8
54/18 = 3/1 = 3
100/25 = 4/1 = 4
Rut gon bieu thuc sau : A=3x5x7x11x13x37-10101 / 1212120+40404
giup minh voi cac ban oi!!!!
bn ơi ghi lại đề bài = phân số đc hk ghi cả nhân hay chia nx khó nhìn lắm!
A=\(\frac{3.5.7.11.13.37-10101}{1212120+40404}\)
A=\(\frac{\left(3.7.11.37.13\right).5-10101}{120.10101+4.10101}\)
A=\(\frac{10101.5-10101}{120.10101+4.10101}\)
A=\(\frac{1.5-1}{120.1+4.1}\)
A=\(\frac{5-1}{120+4}\)
A=\(\frac{4}{120}\)
A=\(\frac{1}{31}\)
# Học tốt
Tính
A= 2100 - 299 - 298 - 297 - .......... - 22 - 2 - 1
\(A=2^{100}-\left(2^{99}+2^{98}+...+2+1\right)\)
Đặt \(B=2^{99}+2^{98}+...+2+1\)
\(\Rightarrow2B=2^{100}+2^{99}+...+2^2+2\)
\(\Rightarrow2B-B=2^{100}-1\Leftrightarrow B=2^{100}-1\)
\(\Rightarrow A=2^{100}-\left(2^{100}-1\right)=1\)
bieu thuc
E=12/84+12/210+12/390+...+12/2100
giai giup to nhe cam on nhieu
giai ro loi giai ho to nhe
cam on cac ban rat nhieu
Ta nu dien vien Nha Phuong hoc Angelababy ( trong runningman)
Ta mot nguoi ma em yeu ( nguoi yeu)
Ta mot hinh anh sexy nao do ?
(Sorry.Minh tim thay 3 de nay tren mang neu ai lam duoc thi tot ko lam thi minh se gian tai day la minh dang thu do trung thuc cua cac ban :) :) :) :) :)...:) :) :) )
( Hay giup minh nhe :( :( )
A=2100-299+298-297+...-23+22-2+1
HELP ME
\(A=2^{100}-2^{99}+2^{98}-2^{97}+....-2^3+2^2-2+1\\ A=\left(2^{100}+2^{98}+...+2\right)-\left(2^{99}+2^{97}+...+1\right)\)
Gọi \(\left(2^{100}+2^{98}+...+2\right)\)là B
\(B=\left(2^{100}+2^{98}+...+2\right)\\ 2B=2^{102}+2^{100}+.....+2^2\\ 2B-B=\left(2^{102}+2^{100}+.....+2^2\right)-\left(2^{100}+2^{98}+...+2\right)\\ B=2^{102}-2\)
Gọi \(\left(2^{99}+2^{97}+...+1\right)\) là C
\(C=\left(2^{99}+2^{97}+...+1\right)\\ 2C=2^{101}+2^{99}+....+2\\ 2C-C=\left(2^{101}+2^{99}+9^{97}+...+2\right)-\left(2^{99}+9^{97}+...+1\right)\\ C=2^{101}-1\)
\(A=B+C\\ =>A=2^{102}-2+2^{101}-1\\ A=2^{101}\left(2+1\right)-3\\ A=2^{101}\cdot3-3\\ A=3\cdot\left(2^{101}-1\right)\)
\(\dfrac{1}{2}A=2^{99}-2^{98}+...-1+\dfrac{1}{2}\\ \Rightarrow A-\dfrac{1}{2}A=2^{100}-\dfrac{1}{2}\\ \Rightarrow A=2^{101}-1\)