A=\(\frac{3}{9.6}+\frac{5}{2.7.9}+\frac{7}{6.7.7}+\frac{8}{3.7.29}\) = \(\frac{1}{18}+\frac{5}{7.18}+\frac{1}{6.7}+\frac{8}{3.7.29}\)

= \(\frac{7+5}{7.18}+\frac{1}{6.7}+\frac{8}{3.7.29}\)=\(\frac{2}{7.3}+\frac{1}{6.7}+\frac{8}{3.7.29}\)= \(\frac{1}{3.7}.\)(\(\frac{2}{1}+\frac{1}{2}+\frac{8}{29}\))=

=\(\frac{1}{21}.\)(\(\frac{116+29+16}{58}\))=\(\frac{1}{21}.\frac{161}{58}=\frac{161}{1218}\)

23/174

A=3/54+5/126+7/294+8/609

=1/18+5/126+1/42+8/609

=2/21+15/406

=23/174

tick cho mik nha

\(\frac{23}{174}\)nha bạn

A=3/54+5/126+7/294+8/609

=1/18+5/126+1/42+8/609

=2/21+15/406

=23/174

tick cho mik nha

=\(\frac{23}{174}\)nha

a = 3/54 + 5/126 + 7/294 + 8/609 + 13/1218

=> a = 3/6.9 + 5/9.14 + 7/14.21 + 8/21.29 + 13/29.42

=> a = 1/6 - 1/9 + 1/9 - 1/14 + 1/14 - 1/21 + 1/21 - 1/29 + 1/29 - 1/42

=> a = 1/6 - 1/42

=> a = 7/42 - 1/42

=> a = 6/42 = 1/7

\(\frac{3}{54}+\frac{5}{126}+\frac{7}{294}+\frac{8}{609}\) 

\(=\frac{3}{6.9}+\frac{5}{9.14}+\frac{7}{14.21}+\frac{8}{21.29}\) 

\(=\frac{1}{6}-\frac{1}{9}+\frac{1}{9}-\frac{1}{14}+\frac{1}{14}-\frac{1}{21}+\frac{1}{21}-\frac{1}{29}\)

\(=\frac{1}{6}-\frac{1}{29}=\frac{23}{174}\)

lm ơn giúp mk nha

làm xong mk tk cho

                                                              23  /  1083

M=3/10+4/45+5/126+6

bấm máy 

ra nghiêm sau

M=\(\frac{25}{54}\)

\(\dfrac{42x45}{5x7}=\dfrac{7x6x5x9}{5x7}=\dfrac{54}{1}=54\)

\(\dfrac{54x56}{7x9}=\dfrac{6x9x7x8}{7x9}=\dfrac{48}{1}=48\)

`(42 xx45)/(5xx7) =( 6xx7xx9xx5)/(5xx7) = 6 xx9 = 54`

`(54xx56)/(7xx9) = (9xx6xx7xx8)/(7xx9) = 6xx8 = 48`

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