\(7^{2x}.49=343\)
\(7^{2x}=343:49\)
\(7^{2x}=7\)
\(7^{2x}=7^1\)
\(2x=1\)
\(x=\frac{1}{2}\)
72x.49 = 343
72x.72 = 343
72x+2 = 343 = 73
=> 2x + 2 = 3
2x = 1
x = 1/2
tìm x thuộcN biết
3 x: 3=81
22x :8=128
7x-1 .49=343
Tính nhanh
A=182.[1+1/3+1/9+1/27/2+2/3+2/9+2/27:4-4/7-4/49-4/343/1-1/7-1/49-1/343]=919191/808080
\(182.\left(\frac{1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}}{2+\frac{2}{3}+\frac{2}{9}+\frac{2}{27}}:\frac{4-\frac{4}{7}+\frac{4}{49}-\frac{4}{343}}{1-\frac{1}{7}+\frac{1}{49}-\frac{1}{343}}\right):\frac{919191}{808080}\)
Tính \(\left(\frac{1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}}{2+\frac{2}{3}+\frac{2}{9}+\frac{2}{27}}\div\frac{4-\frac{4}{7}+\frac{4}{49}-\frac{4}{343}}{1-\frac{1}{7}+\frac{1}{49}-\frac{1}{343}}\right)\div\frac{919191}{808080}\)
Tính A = 1 -\(\frac{1}{7}\)+\(\frac{1}{49}\)-\(\frac{1}{343}\)
B = 4 -\(\frac{4}{7}\)+\(\frac{4}{49}\)-\(\frac{4}{343}\)
Tính nhanh:\(\left(\frac{1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}}{2+\frac{2}{3}+\frac{2}{9}+\frac{2}{27}}:\frac{4-\frac{4}{7}+\frac{4}{49}+\frac{4}{343}}{1-\frac{1}{7}-\frac{1}{49}-\frac{1}{343}}\right):\frac{91919191}{80808080}\)
B = \(\frac{1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}}{2+\frac{2}{3}+\frac{2}{9}+\frac{2}{27}}\) :\(\frac{4+\frac{4}{7}+\frac{4}{49}+\frac{4}{343}}{1+\frac{1}{7}+\frac{1}{49}-\frac{1}{343}}\)
Tính nhanh
Ai Nhanh tk
Tính :
\(\left(\frac{1-\frac{1}{3}+\frac{1}{9}+\frac{1}{21}}{2+\frac{2}{3}+\frac{2}{9}+\frac{2}{27}}:\frac{4-\frac{4}{7}+\frac{4}{49}-\frac{4}{343}}{1-\frac{1}{7}+\frac{1}{49}-\frac{1}{343}}\right):\frac{919191}{808080}\)
7 mũ 2x cộng 1 =343
