Tìm x x+1/10 + x+1/11 + x+1/12 = x+1/13 + x+1/14 04/11/2021 Bởi Everleigh Tìm x x+1/10 + x+1/11 + x+1/12 = x+1/13 + x+1/14
CHÚC BẠN HỌC TỐT!!! Trả lời: $\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}$ $⇔(x+1).\bigg{(}\dfrac{1}{10}+\dfrac{1}{11}+\dfrac{1}{12}-\dfrac{1}{13}-\dfrac{1}{14}\bigg{)}=0$ $⇔\dfrac{7561}{60060}.(x+1)=0$ $⇔x+1=0$ $⇔x=-1$. Bình luận
Đáp án: `(x + 1)/10 + (x + 1)/11 + (x + 1)/12 = (x + 1)/13 + (x + 1)/14` `⇔ (x + 1)/10 + (x – 1)/11 + (x + 1)/12 – (x + 1)/13 – (x + 1)/14 = 0` `⇔ (x + 1) . (1/10 + 1/11 + 1/12 – 1/13 – 1/14)` `⇔ x + 1 = 0` (vì `1/10 + 1/11 + 1/12 – 1/13 – 1/14 \ne 0`) `⇔ x = 0 – 1` `⇔ x = -1` Vậy `x = -1` Bình luận
CHÚC BẠN HỌC TỐT!!!
Trả lời:
$\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}=\dfrac{x+1}{13}+\dfrac{x+1}{14}$
$⇔(x+1).\bigg{(}\dfrac{1}{10}+\dfrac{1}{11}+\dfrac{1}{12}-\dfrac{1}{13}-\dfrac{1}{14}\bigg{)}=0$
$⇔\dfrac{7561}{60060}.(x+1)=0$
$⇔x+1=0$
$⇔x=-1$.
Đáp án:
`(x + 1)/10 + (x + 1)/11 + (x + 1)/12 = (x + 1)/13 + (x + 1)/14`
`⇔ (x + 1)/10 + (x – 1)/11 + (x + 1)/12 – (x + 1)/13 – (x + 1)/14 = 0`
`⇔ (x + 1) . (1/10 + 1/11 + 1/12 – 1/13 – 1/14)`
`⇔ x + 1 = 0` (vì `1/10 + 1/11 + 1/12 – 1/13 – 1/14 \ne 0`)
`⇔ x = 0 – 1`
`⇔ x = -1`
Vậy `x = -1`