tinh
A=(\(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\)):(\(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}\cdot\frac{1}{23}\cdot\frac{1}{1009}\))+1:(30.1009-160)
Tính giá trị biểu thức sau:
A = \(\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right):\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}\cdot\frac{1}{23}\cdot\frac{1}{1009}\cdot\right)+1:\left(30.1009-160\right)\)
=> A= \(\frac{\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}\right).23.7.1009}{\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\right).23.7.1009}\) + \(\frac{1}{30.1009-160}\)
=> A= \(\frac{7.1009+23.1009-23.7}{7.1009+23.1009-23.7+1}\) + \(\frac{1}{7.1009+23.1009-23.7+1}\) = \(\frac{7.1009+23.1009-23.7+1}{7.1009+23.1009-23.7+1}\) = 1.
Hưng ơi có hiểu bài này ko bảo t với!!!!!!!!
B=(\(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\)) : (\(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}\cdot\frac{1}{23}\cdot\frac{1}{1009}\))+1: (30.1009-160)
\(\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right)\): \(\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}\cdot\frac{1}{23}\cdot\frac{1}{1009}\right)\)+ \(\frac{1}{30\cdot1009-160}\)
đặt A là tên biểu thức trên
ta có :
\(A=\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right):\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\right)+\frac{1}{30.1009-160}\)
\(A=\left(\frac{23.1009}{7.23.1009}+\frac{7.1009}{7.23.1009}-\frac{7.23}{7.23.1009}\right):\left(\frac{7.1009}{23.7.1009}+\frac{23.1009}{23.7.1009}-\frac{23.7}{23.7.1009}+\frac{1}{23.7.1009}\right)+\frac{1}{30.1009-160}\)\(A=\frac{23.1009+7.1009-7.23}{7.23.1009}:\frac{7.1009+23.1009-23.7+1}{7.23.1009}+\frac{1}{30.1009-160}\)
\(A=\frac{23.1009+7.1009-7.23}{7.1009+23.1009-23.7+1}+\frac{1}{30.1009-160}\)
\(A=\frac{30.1009-161}{30.1009-160}+\frac{1}{30.1009-160}\)
\(A=\frac{30.1009-160}{30.1009-160}=1\)
nhân hai số đầu với bình phương 23.7.1009 ta có 30109/30110+1/30110=1
Tính giá trị của biểu thức sau: \(\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right):\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}\cdot\frac{1}{23}\cdot\frac{1}{1009}\right)+1:\left(30\cdot1009-160\right)\)
tinh
\(A=\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right):\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\right)+1:\left(30.1009-160\right)\)
A = [ \(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\)] :\(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\)] + 1: [30.1009-160]
Tìm A
Tính giá trị của biểu thức sau:
\(A=\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right):\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\right)+1:\left(30.1009-160\right)\)
tính giá trị biểu thức sau:
A= (\(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\)):(\(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\) )+1:(30.1009-160)
\(A=\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right):\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\right)+1:\left(30.1009-160\right)\)
\(=\frac{23.1009+7.1009-7.23}{7.23.1009}:\frac{7.1009+23.1009-23.7+1}{7.23.1009}+\frac{1}{30.1009-160}\)
\(=\frac{30109}{7.23.1009}.\frac{7.3.1009}{30110}+\frac{1}{30110}\)
\(=\frac{30109}{30110}+\frac{1}{30110}=\frac{30110}{30110}=1\)
Tính giá trị biểu thức
\(B=\left(\frac{1}{7}+\frac{1}{23}-\frac{1}{1009}\right):\left(\frac{1}{23}+\frac{1}{7}-\frac{1}{1009}+\frac{1}{7}.\frac{1}{23}.\frac{1}{1009}\right)+1:\left(30.1009-160\right)\)