1) x+5 / 3x-6 - 1/2 = 2x-3 / 2x-4 = 0 2) 12 / 1-9x^2 = 1-3x / 1+3x - 1+3x / 1-3x (đề bài là giải phương trình ạ ) ( dấu / là phần , dấu ^ là mũ ạ )
2 câu trả lời
Đáp án:
$1)$ S = `{16}`
$2)$ S = `{-1}`
Giải thích các bước giải:
$1)$ $\dfrac{x+5}{3x-6}-\dfrac{1}{2}=\dfrac{2x-3}{2x-4\:}=0$
$⇔-x+16=0$
$⇔16−x=0$
$⇔-x=-16$
$⇔x=16$
Vậy S = `{16}`
$2)$ $\dfrac{12}{1-9x^2}=\dfrac{1-3x}{1+3x}-\dfrac{1+3x}{1-3x}$ `;(x!=+-1/3)`
$⇔\dfrac{12}{\left(1+3x\right)\left(1-3x\right)\:}=\dfrac{\:1-3x}{1+3x\:}-\dfrac{1+3x}{\:1-3x\:\:\:}$
$⇔12=\left(1-3x\right)^2-\left(1+3x\right)^2$
$⇔\left(1-3x\right)^2-\left(1+3x\right)^2=12$
$⇔-12x=12$
$⇔x=-1$
Vậy S = `{-1}`
Đáp án:
$\dfrac{x+5}{3x-6}-\dfrac{1}{2}=\dfrac{2x-3}{2x-4\:}=0$
$⇔-x+16=0$
$⇔16−x=0$
$⇔x=16$
Vậy `S =` `{16}`
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$\dfrac{12}{1-9x^2}=\dfrac{1-3x}{1+3x}-\dfrac{1+3x}{1-3x}$ `;(x!=+-1/3)`
$⇔\dfrac{12}{\left(1+3x\right)\left(1-3x\right)\:}=\dfrac{\:1-3x}{1+3x\:}-\dfrac{1+3x}{\:1-3x\:\:\:}$
$⇔12=\left(1-3x\right)^2-\left(1+3x\right)^2$
$⇔\left(1-3x\right)^2-\left(1+3x\right)^2=12$
$⇔-12x=12$
$⇔x=12:(-12)$
$⇔x=-1$
Vậy `S =` `{-1}`