## Lô nhìn dõ giúp mình

Question

Lô nhìn dõ giúp mình

in progress 0
4 years 2020-11-21T08:12:43+00:00 1 Answers 60 views 0

1. Đáp án:

Bài 1)
1)x=\dfrac{-3}{4}\\ 2) {\left[\begin{aligned}x=\dfrac{1}{6}\\x=\dfrac{2}{3}\end{aligned}\right.}
Bài 2)
$1) \dfrac{1}{3}\\ 2) 0,000001\\ 3)1\\ 4)1\\ 5)4$

Giải thích các bước giải:

Bài 1)
1) \left | x+\dfrac{3}{4} \right |=0\\ \Leftrightarrow x+\dfrac{3}{4}=0\\ \Leftrightarrow x=\dfrac{-3}{4}\\ 2) \left | \dfrac{5}{12}-x \right |+\dfrac{3}{8}=\dfrac{5}{4}\\ \Leftrightarrow \left | \dfrac{5}{12}-x \right |=\dfrac{5}{4}-\dfrac{3}{8}\\ \Leftrightarrow \left | \dfrac{5}{12}-x \right |=\dfrac{10}{8}-\dfrac{3}{8}\\ \Leftrightarrow \left | \dfrac{5}{12}-x \right |=\dfrac{2}{8}=\dfrac{1}{4}\\ \Leftrightarrow {\left[\begin{aligned}\dfrac{5}{12}-x=\dfrac{1}{4}\\\dfrac{5}{12}-x=\dfrac{-1}{4}\end{aligned}\right.}\\ \Leftrightarrow {\left[\begin{aligned}x=\dfrac{5}{12}-\dfrac{1}{4}\\x=\dfrac{5}{12}+\dfrac{1}{4}\end{aligned}\right.}\\ \Leftrightarrow {\left[\begin{aligned}x=\dfrac{5}{12}-\dfrac{3}{12}\\x=\dfrac{5}{12}+\dfrac{3}{12}\end{aligned}\right.}\\ \Leftrightarrow {\left[\begin{aligned}x=\dfrac{2}{12}=\dfrac{1}{6}\\x=\dfrac{8}{12}=\dfrac{2}{3}\end{aligned}\right.}
Bài 2)
$1) \left ( \dfrac{-1}{3} \right )^2:\dfrac{1}{3}=\left ( \dfrac{1}{3} \right )^2:\dfrac{1}{3}=\dfrac{1}{3}\\ 2) [(0,1)^3]^2=(0,001)^2=0,000001\\ 3) \left [ \left ( \dfrac{-1}{27} \right )^0 \right ]^3\\ =1^3=1\\ 4) \left ( \dfrac{1}{7} \right )^7.7^7\\ =\dfrac{1^7}{7^7}.7^7\\ =1\\ 5) (0,25)^4.1024\\ =\dfrac{1}{256}.1024\\ =4$