tìm x biết: 8-|1-3x|=3 |x-1|+3=2.x (0,4x-1,3)^2=5,29 (x-3)^10=(x-30^11 {1/2}^2x-1=1/8

0 bình luận về “tìm x biết: 8-|1-3x|=3 |x-1|+3=2.x (0,4x-1,3)^2=5,29 (x-3)^10=(x-30^11 {1/2}^2x-1=1/8”

1. 8-|1-3x|=3

   ⇔ |1-3x|=5

   ⇔ \(\left[ \begin{array}{l}1-3x=5\\1-3x=-5\end{array} \right.\) 

   ⇔ \(\left[ \begin{array}{l}3x=-4\\3x=6\end{array} \right.\) 

   ⇔ \(\left[ \begin{array}{l}x=-\frac{4}{3} \\x=2\end{array} \right.\) 

   |x-1|+3=2.x

   ⇔ |x-1|=2x-3

   ⇔ \(\left[ \begin{array}{l}x-1=2x-3\\x-1=3-2x\end{array} \right.\) 

   ⇔ \(\left[ \begin{array}{l}-x=-2\\3x=4\end{array} \right.\) 

   ⇔\(\left[ \begin{array}{l}x=2\\x=\frac{4}{3} \end{array} \right.\) 

   (0,4x-1,3)²=5,29

   ⇔ \(\left[ \begin{array}{l}0,4x-1,3=2,3\\0,4x-1,3=-2,3\end{array} \right.\) 

   ⇔ \(\left[ \begin{array}{l}0,4x=3,6\\0,4x=2,6\end{array} \right.\) 

   ⇔ \(\left[ \begin{array}{l}x=9\\x=6,5\end{array} \right.\) 

   (x-3)^10=(x-3)^11

   ⇔ (x-3)^10 – (x-3)^11 = 0

   ⇔ (x-3)^10.[1-(x-3)] =0

   ⇔ (x-3)^10.(1-x+3) = 0

   ⇔ (x-3)^10.(4-x)=0

   ⇔ \(\left[ \begin{array}{l}(x-3)^{10}=0\\4-x=0\end{array} \right.\)

   ⇔ \(\left[ \begin{array}{l}x=3\\x=4\end{array} \right.\) 

   ($\frac{1}{2}$ )²x – 1 = 1/8

   ⇔ $\frac{1}{4}$x = 9/8

   ⇔ x = $\frac{9}{2}$  

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2. Đáp án:

    

   Giải thích các bước giải:

   a/ $8-|1-3x|=3$
   ⇔ $|1-3x|=8-3=5$
   ⇔ \(\left[ \begin{array}{l}1-3x=5\\1-3x=-5\end{array} \right.\)
   ⇔ \(\left[ \begin{array}{l}x=-\frac{4}{3}\\x=2\end{array} \right.\)

   b/ $|x-1|+3=2x$
   ⇔ $|x-1|=2x-3$
   ⇔ \(\left[ \begin{array}{l}x-1=2x-3\\x-1=-2x+3\end{array} \right.\)
   ⇔ \(\left[ \begin{array}{l}x=2\\x=\frac{4}{3}\end{array} \right.\)

   c/ $(x-3)^{10}=(x-3)^{11}$
   ⇔ \(\left[ \begin{array}{l}x-3=1\\x-3=0\end{array} \right.\)
   ⇔ \(\left[ \begin{array}{l}x=4\\x=3\end{array} \right.\)

   d/ $(\frac{1}{2})^2.x-1=\frac{1}{8}$
   ⇔ $\frac{1}{4}.x=\frac{1}{8}+1=\frac{9}{8}$
   ⇔ $x=\frac{9}{8}:\frac{1}{4}=\frac{9}{2}$
   Chúc bạn học tốt !!

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