\(C,\dfrac{1}{2}.\dfrac{3}{4}+\dfrac{1}{2}.\dfrac{1}{4}=\dfrac{1}{2}.\left(\dfrac{3}{4}+\dfrac{1}{4}\right)\)

\(=\dfrac{1}{2}.\dfrac{4}{4}=\dfrac{1}{2}.1=\dfrac{1}{2}\)

\(D,\dfrac{11}{3}.\dfrac{26}{7}-\dfrac{26}{7}.\dfrac{8}{3}=\dfrac{26}{7}.\left(\dfrac{11}{3}-\dfrac{8}{3}\right)\)

\(=\dfrac{26}{7}.\dfrac{3}{3}=\dfrac{26}{7}.1=\dfrac{26}{7}\)

\(\dfrac{8}{\sqrt{x}-2}-\dfrac{\sqrt{x}+26}{x-4}\\ đk:x\ne4;x>0\\ =\dfrac{8\left(\sqrt{x}+2\right)-\sqrt{x}-26}{x-4}\\ =\dfrac{8\sqrt{x}+16-\sqrt{x}-26}{x-4}\\ =\dfrac{7\sqrt{x}-10}{x-4}\)

Ta có: (x + 2)(x + 4) > (x – 2)(x + 8) + 26

      ⇔ x 2  + 6x + 8 >  x 2  + 6x + 10

      ⇔  x 2  + 6x -  x 2  - 6x > 10 - 8

       ⇔ 0x > 2

Vậy bất phương trình vô nghiệm.

X x 2 + 8 = 26

X x 2 = 18

      X = 18 : 2

      X = 9

Đáp án cần chọn là A

174 x 36 - 174 x 26
= 174 x ( 36 - 26 )
= 174 x 10
= 1740

2/3 x 4/5 + 1/8 x 2/3
= 2/3 x ( 4/5 + 1/8 )
= 2/3 x 37/40
= 37/60

`=174xx(36-26)`

`=174xx10=1740`

`=2/3xx(4/5+1/8)`

`=2/3xx37/40=37/60`

174 x ( 36-26) = 1740

\(\dfrac{2}{3}x\left(\dfrac{4}{5}+\dfrac{1}{8}\right)=\dfrac{2}{3}x\dfrac{37}{40}=\dfrac{37}{60}\)

toán lp 1 ???

toán lớp 1 sao học ghê vậy lm đc cả x vs ^ luôn ô mai gi gứ chóp bạn nào lớp 1 mà giải đc bài này luôn ?????

\(=\dfrac{29}{13}\cdot\dfrac{13}{29}\cdot4\cdot\dfrac{21}{8}\cdot\dfrac{8}{21}=4\)

bài này mik ra \(\dfrac{39}{29}\) ko bt đúng ko :)