Toán 10/x+5 = 7x+1/x+5 – 3 /3-5x/=2x+1 giải phương trình 08/10/2021 By Hailey 10/x+5 = 7x+1/x+5 – 3 /3-5x/=2x+1 giải phương trình
ĐK: `x \ne -5` `10/(x+5)=(7x+1)/(x+5)-3` `<=> 10=7x+1-3(x+5)` `<=>10=7x+1-3x-15` `<=>10=4x-14` `<=> 4x=24` `<=>x=6` (TM) Vậy `S={6}`. . `|3-5x|=2x+1` TH1: `3-5x >=0 <=> x <= 3/5` `3-5x=2x+1` `<=>-7x=-2` `<=> x =2/7` (TM) TH2: `3-5x <0 <=> x >3/5` `5x-3=2x+1` `<=> 3x=4` `<=>x=4/3` (TM) Vậy `S={2/7 ;4/3}`. Trả lời
Đáp án + Giải thích các bước giải: `a//(10)/(x+5)=(7x+1)/(x+5)-3` `(ĐKXĐ:x\ne-5)` `⇔(10)/(x+5)=(7x+1)/(x+5)-(3(x+5))/(x+5)` `⇔7x+1-3(x+5)=10` `⇔7x+1-3x-15=10` `⇔7x-3x=-1+15+10` `⇔4x=24` `⇔x=6(TM)` Vậy `S={6}` `b//|3-5x|=2x+1` `( ĐK:x≥-\frac{1}{2})` `⇔` \(\left[ \begin{array}{l}3-5x=2x+1\\3-5x=-2x-1\end{array} \right.\) `⇔` \(\left[ \begin{array}{l}-5x-2x=-3+1\\-5x+2x=-3-1\end{array} \right.\) `⇔` \(\left[ \begin{array}{l}-7x=-2\\-3x=-4\end{array} \right.\) `⇔` \(\left[ \begin{array}{l}x=\frac{2}{7}(TM)\\x=\frac{4}{3}(TM)\end{array} \right.\) Vậy `S={(2)/(7);(4)/(3)}` Trả lời
ĐK: `x \ne -5`
`10/(x+5)=(7x+1)/(x+5)-3`
`<=> 10=7x+1-3(x+5)`
`<=>10=7x+1-3x-15`
`<=>10=4x-14`
`<=> 4x=24`
`<=>x=6` (TM)
Vậy `S={6}`.
.
`|3-5x|=2x+1`
TH1: `3-5x >=0 <=> x <= 3/5`
`3-5x=2x+1`
`<=>-7x=-2`
`<=> x =2/7` (TM)
TH2: `3-5x <0 <=> x >3/5`
`5x-3=2x+1`
`<=> 3x=4`
`<=>x=4/3` (TM)
Vậy `S={2/7 ;4/3}`.
Đáp án + Giải thích các bước giải:
`a//(10)/(x+5)=(7x+1)/(x+5)-3` `(ĐKXĐ:x\ne-5)`
`⇔(10)/(x+5)=(7x+1)/(x+5)-(3(x+5))/(x+5)`
`⇔7x+1-3(x+5)=10`
`⇔7x+1-3x-15=10`
`⇔7x-3x=-1+15+10`
`⇔4x=24`
`⇔x=6(TM)`
Vậy `S={6}`
`b//|3-5x|=2x+1` `( ĐK:x≥-\frac{1}{2})`
`⇔` \(\left[ \begin{array}{l}3-5x=2x+1\\3-5x=-2x-1\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}-5x-2x=-3+1\\-5x+2x=-3-1\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}-7x=-2\\-3x=-4\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=\frac{2}{7}(TM)\\x=\frac{4}{3}(TM)\end{array} \right.\)
Vậy `S={(2)/(7);(4)/(3)}`