tinh tong S = /(1-11)+(1-10)+...+(1-2)/
tinh tong S=/(1-11)+(1-10)+........+(1-2)/ ta duoc ket qua S
1.Cho tong S=5+8+11+14...
tim so hang thu 100 cua day
2.Tinh tong S=1+2+22+...+210
tinh tong S=I(1-11)+(1-10)+........+(1-2)Ita duoc ket qua S=
trình bày cách giải giùm mình nha
Từ S ta suy ra 10+9+8+7+6+5+4+3+2+1=55
Vậy S=55
tinh tong s=1/2^2+1/3^2+...+ 1/10^2
S=1+101+102+...+1020
TINH TONG
\(S=1+10^1+10^2+...+10^{20}\)
\(10S=10+10^2+10^3+...+10^{21}\)
\(10S-S=\left(10+10^2+...+10^{21}\right)-\left(1+10+...+10^{20}\right)\)
\(9S=10^{21}-1\)
\(S=\frac{10^{21}-1}{9}\)
tinh tong S=1+2+22...+210
2.S = 2 + 22 + 23 + ...+ 211
Lấy 2.S - S = (2 + 22 + 23 + ...+ 211) - (1 + 2 + 22 + ...+ 210)
=> S = 211 - 1
S = 1+2+22+23+...+210
2S = 2+22+23+24+...+211
2S-S = S = 2+22+23+24+...+211-1-2-22-23-...-211
S = 211-1
S = 2048-1
S = 2047
tinh tong:
a)S=1-6+11-16+21-26+........+176-181
b)S=1-3+3^2-3^3+.......-3^2007+3^2008
tinh tong S=1+2^2+3^3=...+10^10 bang cach su dung cau len lap For...do
uses crt;
var i,j:integer;
s:real;
{----------chuong-trinh-con---------------}
function luythua(x,y:integer):real;
var lt:real;
i:integer;
begin
lt:=1;
for i:=1 to y do
lt:=lt*x;
luythua:=lt;
end;
{---------------chuong-trinh-chinh---------------------}
s:=0;
for i:=1 to 10 do
for j:=1 to 10 do
if i=j then s:=s+luythua(i,j);
writeln(s:0:0);
readln;
end.
A=1 2 3...9 10 11...100
Tinh tong cac chu so cua A