so sánh
\(\frac{10^8+6}{10^8-7}\)
\(\frac{10^8+6}{10^8-7}\)
1. So Sánh: \(A=\frac{10^7+5}{10^7-8};B=\frac{10^8+6}{10^8-7}\)
dễ thôi
A=\(\frac{10^7+5}{10^7-8}=\frac{10^7-8+13}{10^7-8}=1+\frac{13}{10^7-8}\)
B=\(\frac{10^8+6}{10^8-7}=\frac{10^8-7+13}{10^8-7}=1+\frac{13}{10^8-7}\)
\(10^8>10^7nen10^8-7>10^7-8\)
=> \(\frac{13}{10^8-7}< \frac{13}{10^7-8}hayB< A\)
\(\frac{10^7+5}{10^7-8}=\frac{10^7-8+13}{10^7-8}=1-\frac{13}{10^7-8}\);\(\frac{10^8+6}{10^8-7}=\frac{10^8-7+13}{10^8-7}=1-\frac{13}{10^7-7}\)
Vì \(\frac{13}{10^8-8}< \frac{13}{10^7-7}\)nên A>B
Ta có :
\(A=\frac{10^7+5}{10^7-8}=\frac{10^7-8+13}{10^7-8}=1+\frac{13}{10^7-8}\)
\(B=\frac{10^8+6}{10^8-7}=\frac{10^8-7+13}{10^8-7}=1+\frac{13}{10^8-7}\)
Mà \(\frac{13}{10^7-8}>\frac{13}{10^8-7}\left(10^7-8< 10^8-7\right)\)
\(\Rightarrow1+\frac{13}{10^7-8}>1+\frac{13}{10^8-7}\)
\(\Rightarrow A< B\)
Vậy \(A< B\)
~ Ủng hộ nhé
So sánh:
M=\(\frac{10^7+5}{10^7-8}\) và N=\(\frac{10^8+6}{10^8-7}\)
\(M=\frac{10^7+5}{10^7-8}=\frac{10^7-8+13}{10^7-8}=1+\frac{13}{10^7-8}\)
\(N=\frac{10^8+6}{10^8-7}=\frac{10^8-7+13}{10^8-7}=1+\frac{13}{10^8-7}\)
Ta có \(10^8-7>10^7-8\) \(=>\frac{13}{10^8-7}< \frac{13}{10^7-8}\) \(=>M< N\)
Vậy M<N
n<m nha ban
chuc ban hoc gioi
tk cho minh nha
So sánh A và B:
a)A=\(\frac{10^7+5}{10^7-8}\); B=\(\frac{10^8+6}{10^8-7}\)
\(A=\frac{10^7+5}{10^7-8}=\frac{\left(10^7-8\right)+13}{10^7-8}=1+\frac{13}{10^7-8}\)
\(B=\frac{10^8+6}{10^8-7}=\frac{\left(10^8-7\right)+13}{10^8-7}=1+\frac{13}{10^8-7}\)
Vì \(10^7-8< 10^8-7\) nên \(\frac{13}{10^7-8}>\frac{13}{10^8-7}\)
\(\Rightarrow1+\frac{13}{10^7-8}>1+\frac{13}{10^8-7}\) do đó \(A>B\)
Cho \(S=\frac{3}{2}+\frac{4}{3}+\frac{5}{4}+\frac{6}{5}+\frac{7}{6}+\frac{8}{7}+\frac{9}{8}+\frac{10}{9}+\frac{11}{10}+\frac{12}{11}\)
So sánh S với 10
Ta có :
\(S=\frac{3}{2}+\frac{4}{3}+\frac{5}{4}+\frac{6}{5}+\frac{7}{6}+\frac{8}{7}+\frac{9}{8}+\frac{10}{9}+\frac{11}{10}+\frac{12}{11}\)
\(S=\frac{2+1}{2}+\frac{3+1}{3}+\frac{4+1}{4}+...+\frac{11+1}{11}\)
\(S=\left(1+\frac{1}{2}\right)+\left(1+\frac{1}{3}\right)+\left(1+\frac{1}{4}\right)+...+\left(1+\frac{1}{11}\right)\)
\(S=\left(1+1+1+...+1\right)+\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{11}\right)\)
\(S=10+\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{11}\right)>10\)
\(\Rightarrow\)\(S>10\)
Vậy \(S>10\)
Chúc bạn học tốt ~
So sánh A=\(\frac{10^7+8}{10^7-8}\)B=\(\frac{10^8+8}{10^7-8}\)
10^7+8/10^7-8<10^8+8/10^7-8
cho mik nhé
thnks !!!!!!!!!!!!!
So sánh A và B biết:
a) \(A=\frac{3}{83}+\frac{7}{84};B=\frac{7}{83}+\frac{3}{84}\)
b) \(A=\frac{10^7+5}{10^7-8};B=\frac{10^8+6}{10^8-7}\)
So sánh:
A = \(\frac{10^7+1}{10^8+1}\) và B = \(\frac{10^6+1}{10^7+1}\)
Ta có: \(10A=10\left(\frac{10^7+1}{10^8+1}\right)=\frac{10^8+10}{10^8+1}=\frac{10^8+1+9}{10^8+1}=1+\frac{9}{10^8+1}\)
\(10B=\frac{10^7+10}{10^7+1}=\frac{10^7+1+9}{10^7+1}=1+\frac{9}{10^7+1}\)
Vì \(10^8+1>10^7+1\Rightarrow\frac{9}{10^8+1}< \frac{9}{10^7+1}\)
\(\Rightarrow10A< 10B\)
\(\Rightarrow A< B\)
Có nhiều lắm !! Cậu cứ suy nghĩ là ra !
So sánh A = 10^7+5/10^7-8 và 10^8+6/10^8-7
so sánh
A= 10^7+8/10^7-8 và B=10^8+6/10^8-7