Tinh tong
a) 1-2+3-4+.....+2016-2017
b) 0-2+4-6+...+2016-2018
Ai lam dc, dung minh cho 2 tick
2 . Tim so nguyen x , biet:
a ) 121 - 2 . ( x + 6 ) = /- 11/ . 2016^0
b ) 2 ./x-1/ - (- 3 ) = 3^2017 : 3 ^ 2016
Ai lam nhanh va dung minh se tick cho nha .
Cac ban oi , hay chuc minh thi tot duoc ko ? hihi (^.^)
tinh 2/2*4 + 2/4*6 + 2/6*8 + ......... 2/2014*2016 = ( viet ket qua duoi dan phan so toi gian) ket qua la 1007/2016 viet cach lam ra ho minh nhe
Ta co : 2/2*4+2/4*6+2/6*8+.....+2/2014*2016
=1/2-1/4+1/4-1/6+1/6-1/8...+1/2014-1/2016
=1/2-1/2016=1007/2016
2/2 x 4 + 2/2 x 6 +2/6 x 8 + ...................... +2/2014 x 2016
=2/2 - 2/4 +2/2 -2/6 + 2/6 +2/8 + .................+2/2014 - 2/2016
rut gon ta duoc con lai: 2/2-2/2016
=1-1/1008
=1007/1008
tk minh nha
chuc ban hoc tot
happy valentine's day
dap an cua ban sai roi do dap an la 1007/1008
Cho A=1/2!+2/3!+3/4!+...+2015/2016!
Chung minh :A<1
cach lam day du thi minh se tick
Cho A=1/2!+2/3!+3/4!+...+2015/2016!
Chung minh :A<1
cach lam day du thi minh se tick
tinh nhanh: 1^2016+2^2016+3^2016+.......+10^2016/2^2016+4^2016+6^2016+.....+20^2016
\(2^{2016}+4^{2016}+6^{2016}+...+20^{2016}=2^{2016}\left(1+2^{2016}+3^{2016}+...+10^{2016}\right)\)
Do đó:
\(A=\frac{1^{2016}+2^{2016}+3^{2016}+...+10^{2016}}{2^{2016}+4^{2016}+6^{2016}+...+20^{2016}}=\frac{1}{2^{2016}}\)
ai giai giup minh voi
Cho A=75(4^0+4+4^2+4+...+4^2015)-25
a) CM: A chia het cho 4^2016
b) tim du A:4^2017
ai lam duoc minh tick cho
a) 75(4^0+4+4^2+...+4^2015)-15=75((4^1+4^2015)+...+(4^1007+4^1008)+1+4^1006)) chia hết cho 2016
b) 1002
a,A=(6:3/5 -1và1/6x6/7):(4và1/5x10/11+5và2/11
b,B=(1và1/2) x(1và1/3)x(1và1/4)x...(1và1/2016)
c,C=5và9/10:3/2-(2và1/3x4và1/2x2và1/3:7/4
d,D=1/2+1/6++1/12+1/20+1/30+1/42+1/56
Bạn nào giải dc đầu tiên minh tick cho !
Neu 4+2+3 =5
8+4+6 = 10
3+2+1=2
Thi 6+4+2=
Ai tra loi duoc minh se tick . Tinh ca minh do nha neu minh tra loi dc thi phai tick cho minh do,
Chuc cac ban tra loi tot nha minh se tick cho ban ao dung va nhanh nhat khong can cach giai
A=4+2^2+2^3+...+2^20
tinh A bang bao nhieu. Nho ghi cach lam nha
lam dung minh tick cho
\(A=4+2^2+2^3 +...+2^{20}\)
\(\Rightarrow2A=2^3+2^3+2^4+...+2^{21}\)
\(\Rightarrow2A-A=2^{21}+2^3+2^3-4-2^2\)
\(\Rightarrow A=2^{21}+2^3+2^3-4-2^2\)
A=4+22+23+....+220
=(22+22)+23+..+220
=23+23+...+220
=24+24+..+220
làm tương tự như thế
=> A=221
A=4+2^2+2^3+...............+2^20
2A=8+2^3+2^4+2^5+................+2^21
2A-A=2^21+8-4-2^2
A=2^21+4-2^2
A=2^21+4-4
A=2^21
t i c k nha bạn