So sánh A= \(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+...+\frac{1}{100}\)với 1
Cho \(A=\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{99}+\frac{1}{100}\)SO SÁNH A VỚI 1
\(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+.....+\frac{1}{99}+\frac{1}{100}\)so sánh với 1
a, Cho A=\(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{99}+\frac{1}{100}\) . So Sánh A với 1
b, B=\(\frac{1}{11}+\frac{1}{12}+...+\frac{1}{20}\). So sánh B với \(\frac{1}{2}\)
c, cho M=\(\frac{2013}{2014}+\frac{2014}{2015}\)và N=\(\frac{2013+2014}{2014+2015}\). So sánh M và N
Câu a, p/s cuối cùng là \(\frac{1}{100}\)nha mí bn
a) Ta có :
\(A=\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+...+\frac{1}{100}\)
\(>\frac{1}{10}+\frac{1}{100}.90=\frac{1}{10}+\frac{90}{100}=1\)
vậy A > 1
b) \(B=\frac{1}{11}+\frac{1}{12}+...+\frac{1}{20}\)
\(>\frac{1}{20}+\frac{1}{20}+...+\frac{1}{20}=\frac{1}{20}.10=\frac{1}{2}\)
Vậy B > \(\frac{1}{2}\)
Cho A =\(\frac{1}{10}\)+ \(\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{100}\)Hãy so sánh A với \(\frac{1}{2}\)
\(A=\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{100}\)
\(A< \frac{1}{10.11}+\frac{1}{11.12}+...+\frac{1}{100.101}\)
\(A< \frac{1}{10}-\frac{1}{11}+\frac{1}{11}-\frac{1}{12}+...+\frac{1}{100}-\frac{1}{101}\)
\(A< \frac{1}{10}-\frac{1}{101}=\frac{101}{1010}-\frac{10}{1010}=\frac{91}{1010}< \frac{505}{1010}\)
\(A< \frac{1}{2}\)
so sánh
\(\frac{100}{10^{11}}+\frac{100}{10^{12}}va\frac{99}{10^{11}}+\frac{101}{10^{12}}\)
\(\frac{10^{10}+1}{10^{11}+1}va\frac{10^{11}+1}{10^{12}+1}\)
s2 Lắc Lư s2 cko hỏi ôg lp mấy z?
CHO \(A=\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+\frac{1}{14}+...+\frac{1}{99}+\frac{1}{100}\)
SO SÁNH A VỚI 1 GIÚP MÌNH GIẢI ĐẦY ĐỦ NHÉ ! THANKS
A= 1/10+1/11+1/12+1/13+...........+1/99+1/100
2A=1/9+1/10+1/11+1/12+...........+1/98+1/99
2A-A=(1/10+1/11+1/12+1/13+.............+1/99+1/100)-(1/9+1/10+1/11+1/12+............1/98+1/99)
A=1/100-1/9
So sánh:
\(A=\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{49.50}\)và \(B=\frac{1}{10}+\frac{1}{11}+\frac{1}{12}+...+\frac{1}{100}\)
Cho \(A=\frac{10^{11}-1}{10^{12}-1};B=\frac{10^{10}+1}{10^{11}+1}\)
So sánh A và B
( xét A và B so sánh với 1 nhé)
Có : 10A = 10.(10^11-1)/10^12-1 = 10^12-10/10^12-1
Vì : 0 < 10^12-10 < 10^12-1 => 10A < 1 (1)
10B = 10.(10^10+1)/10^11+1 = 10^11+10/10^11+1
Vì : 10^11+10 > 10^11+1 > 0 => 10B > 1 (2)
Từ (1) và (2) => 10A < 10B
=> A < B
Tk mk nha
\(A=\frac{10^{11}-1}{10^{12}-1}\)
\(B=\frac{10^{10}+1}{10^{11}+1}\)
Mà \(\frac{10^{11}-1}{10^{12}-1}< 1\); \(\frac{10^{10}+1}{10^{11}+1}< 1\)
\(\Rightarrow\)\(A,B< 1\)
Ta có:
\(10^{11}-1>10^{10}+1\); \(10^{12}-1>10^{11}+1\)
\(\Rightarrow A>B\)
Vậy A > B
Có : 10A = 10^12-10/10^12-1 = 1 - 9/10^12-1 < 1
10B = 10^11+10/10^11+1 = 1 + 9/10^11+1 > 1
=> 10A < 10B
=> A < B
Tk mk nha
\(A=\frac{10^{11}-1}{10^{12}-1}B=\frac{10^{10}+1}{10^{11}+1}\)
so sánh giúp mình với