Đáp án:
`↓↓`
Giải thích các bước giải:
`a) `
`(81^4. 3^10. 27^5 : 3^12)/(9^9 :9^3. 243^2)`
`=((3^4)^4. 3^10. (3^3)^5 :3^12)/((3^2)^9 :(3^2)^3. (3^5)^2)`
`=(3^16. 3^10. 3^15 :3^12)/(3^18 : 3^6. 3^10)`
`=(3^(41): 3^12)/(3^(28): 3^6)=(3^(29))/(3^(22))=3^7`=2187`
`b)`
`|2-3/2. x|-4=x+2`
`=> |2-3/2. x|=x+2+4`
`=> |2-3/2. x|=x+6`
`=>` \(\left[ \begin{array}{l}2-\dfrac{3}{2}x=x+6\\2-\dfrac{3}{2}x=-x-6\end{array} \right.\) `=>` \(\left[ \begin{array}{l}2-6=x+\dfrac{3}{2}x\\2+6=-x+\dfrac{3}{2}x\end{array} \right.\) `=>` \(\left[ \begin{array}{l}-4=\dfrac{5}{2}x\\8=\dfrac{1}{2}x\end{array} \right.\)
`=>` \(\left[ \begin{array}{l}x=\dfrac{-8}{5}\\x=16\end{array} \right.\)
