câu 1: giải phương trình a. x-2/x+2+3/x-2=x2-11/x2-4

2 bình luận về “câu 1: giải phương trình a. x-2/x+2+3/x-2=x2-11/x2-4”

1. $\dfrac{x – 2}{x + 2}$ $\text{+}$ $\dfrac{3}{x – 2}$ $\text{=}$ $\dfrac{x^{2} – 11}{x^{2} – 4}$

   $\Leftrightarrow$ $\dfrac{(x – 2)(x – 2)}{(x + 2)(x – 2)}$ $\text{+}$ $\dfrac{3(x + 2)}{(x – 2)(x + 2)}$ $\text{=}$ $\dfrac{x^{2} – 11}{(x – 2)(x + 2)}$

   $\Leftrightarrow$ $\dfrac{(x – 2)(x – 2)}{(x + 2)(x – 2)}$ $\text{+}$ $\dfrac{3(x + 2)}{(x – 2)(x + 2)}$ $\text{-}$ $\dfrac{x^{2} – 11}{(x – 2)(x + 2)}$ $\text{= 0}$

   $\Leftrightarrow$ $\dfrac{(x – 2)(x – 2) + 3(x + 2) – x^{2} + 11}{(x + 2)(x – 2)}$ $\text{= 0}$

   $\Leftrightarrow$ $\text{(x – 2)(x – 2) + 3(x + 2) – $x^{2}$ + 11}$ $\text{= 0}$

   $\Leftrightarrow$ $\text{$x^{2}$ – 2x – 2x + 4 + 3x + 6 – $x^{2}$ + 11}$ $\text{= 0}$

   $\Leftrightarrow$ $\text{- x + 21}$ $\text{= 0}$

   $\Leftrightarrow$ $\text{- x}$ $\text{= – 21}$

   $\Leftrightarrow$ $\text{ x}$ $\text{= 21}$

   $\text{Vậy S =}$ {$\text{21}$}

   Trả lời
2. Giải đáp:

    

   Lời giải và giải thích chi tiết:

    (x-2)/(x+2)+3/(x-2)=(x^2-11)/x^2-4(ĐKXĐ x ne +- 2)

   <=>((x-2)(x-2))/((x+2)(x-2))+ (3(x+2))/((x+2)(x-2))=(x^2-11)/((x-2)(x+2)

   <=> (x-2)(x-2)+3(x+2)=x^2-11

   <=>x^2-4x+4+3x+6=x^2-11

   <=>x^2-x^2-4x+3x=-11-6-4

   <=>-x=-21

   <=>x=21(TM)

   Trả lời