RÚT GỌN PHÂN SỐ A = 9×11+32×9 PHẦN 23×15+12×23 B =10×11+50×55+70×77 PHẦN 10×12+55×60+77×84

2 câu trả lời

Đáp án + Giải thích các bước giải:

`A=(9xx11+32xx9)/(23xx15+12xx23)`

`A=(9xx(11+32))/(23xx(15+12))`

`A=(9xx43)/(23xx27)`

`A=(1xx43)/(23xx3)`

`A=43/69`

$\\$

`B=(10xx11+50xx55+70xx77)/(10xx12+55xx60+77xx84)`

`B=(10xx11+5xx10xx5xx11+7xx10xx7xx11)/(10xx12+5xx11xx12xx5+7xx11xx12xx7)`

`B=(10xx11+25xx10xx11+49xx10xx11)/(10xx12+11xx12xx25+49xx11xx12)`

`B=(10xx11xx(1+25+49))/(10xx12+11xx12xx(25+49)`

`B=(10xx11xx75)/(10xx12+11xx12xx74)`

`B=(10xx11xx75)/(12xx(10+11xx74))`

`B=(10xx825)/(12xx824)`

`B=(5xx825)/(6xx824)`

`B=4125/4944`

`B=1375/1648`

$ A = \dfrac{9.11+32.9}{23.15+12.23} = \dfrac{9.(32+11)}{23.(15+12)}=\dfrac{9.43}{23.27} = \dfrac{9.43}{23.3.9} = \dfrac{43}{69} $

$ B = \dfrac{10.11+50.55+70.77}{10.12+55.60+77.84} = \dfrac{10.11+5.10.111+7.10.11}{11.12+5.11.12+7.11.12} = \dfrac{10.11(1+55+7)}{11.12(1+5+7)}=\dfrac{10.63}{12.13} =\dfrac{630}{156}=\dfrac{105}{26}  $