Phương pháp giải:

Trừ nhẩm các số rồi điền kết quả thích hợp vào chỗ trống.

Lời giải chi tiết:

13 − 9 = 4            13 − 8 = 5

13 − 5 = 8            13 − 6 = 7

13 − 4 = 9            13 − 7 = 6

13 − 3 − 2 = 8      13 − 5 = 8

có ai làm đc kkkông

\(\left[5^3.\left(3x+2\right)\right]:13=5^5:\left(13^5:13^4\right)\)

\(\left[5^3\left(3x+2\right)\right]:13=5^5:13\)

\(\left[5^3\left(3x+2\right)\right]:13=\frac{3125}{13}\)

\(\left[5^3\left(3x+2\right)\right]=3125\)

\(3x+2=3125:5^3\)

\(3x+2=25\)

\(3x=25-2\)

\(3x=23\)

\(x=\frac{23}{3}\)

\(5^3.\left(3x+2\right):13=5^5:\left(13^5:13^4\right)\)

\(5^3.\left(3x+2\right):13=3125:13\)

\(5^3.\left(3x+2\right):13=\frac{3125}{13}\)

125 . ( 3x + 2 ) : 13 =\(\frac{3125}{13}\)

125 . ( 3x + 2 ) =\(\frac{3125}{13}.\frac{13}{1}=3125\)

3x + 2              = 3125 : 125

3x + 2              = 25

3x                    = 25 -2

3x                    = 23

x                    =  23 : 3 

x                    = \(\frac{23}{3}\)

bài này tui làm cho cậu cậu tick rồi mà

\(\left[5^3\left(3x+2\right)\right]:13=5^5:\left(13^5:13^4\right)\)

\(\left[5^3\left(3x+2\right)\right]:13=5^5:13\)

\(5^3\left(3x+2\right)=5^5:13.13\)

\(5^3\left(3x+2\right)=5^5\)

\(3x+2=5^5:5^3\)

\(3x+2=25\)

\(3x=25-2\)

\(3x=23\)

\(\Rightarrow x=\frac{23}{3}\)

 ( 375x+250 ) :13=3125;13

375x+250=3125

375x=2875

x=23/3

\(\frac{5}{9}.\frac{7}{13}+\frac{5}{9}.\frac{9}{13}-\frac{5}{9}.\frac{3}{13}\)

\(=\frac{5}{9}.\left(\frac{7}{13}+\frac{9}{13}-\frac{3}{13}\right)\)

\(=\frac{5}{9}.\frac{13}{13}=\frac{5}{9}.1=\frac{5}{9}\)

_Vi hạ_

\(\dfrac{5}{9}\cdot\dfrac{7}{13}+\dfrac{5}{9}\cdot13-\dfrac{5}{9}\cdot\dfrac{3}{13}\)

\(=\dfrac{5}{9}\cdot\left(\dfrac{7}{13}-\dfrac{3}{13}+13\right)\)

\(=\dfrac{5}{9}\cdot\left(\dfrac{4}{13}+13\right)\)

\(=\dfrac{5}{9}\cdot\dfrac{173}{13}\)

\(=\dfrac{865}{117}\)

=5/9(7/13+13-3/13)

=5/9*(13+4/13)

=5/9*173/13=865/117

\(\dfrac{5}{9}\cdot\dfrac{-7}{13}+\dfrac{5}{9}\cdot\dfrac{-9}{13}+\dfrac{5}{9}\cdot\dfrac{3}{13}\)

\(=\dfrac{5}{9}\cdot\left(\dfrac{-7}{13}+\dfrac{-9}{13}+\dfrac{3}{13}\right)\)

\(=\dfrac{5}{9}\cdot\left(-1\right)\)

\(=-\dfrac{5}{9}\)

ta có \(\frac{\frac{4}{5}-\frac{4}{11}+\frac{4}{13}}{\frac{9}{5}-\frac{9}{11}+\frac{9}{13}}+\frac{\frac{5}{7}+\frac{5}{11}-\frac{5}{13}}{\frac{9}{7}+\frac{9}{11}-\frac{9}{13}}\)

       \(=\frac{4\left(\frac{1}{5}-\frac{1}{11}+\frac{1}{13}\right)}{9\left(\frac{1}{5}-\frac{1}{11}+\frac{1}{13}\right)}+\frac{5\left(\frac{1}{7}+\frac{1}{11}-\frac{1}{13}\right)}{9\left(\frac{1}{7}+\frac{1}{11}-\frac{1}{13}\right)}\)

           \(=\frac{4}{9}+\frac{5}{9}=\frac{9}{9}=1\)

Câu trả lời là \(\frac{5}{9}\)phải không ?

\(\frac{5}{9}\)