Tìm $x;k$ : $x^2$ $+$ $2x$ $+$ $1$ $=$ $5k$ 24/10/2021 Bởi Maria Tìm $x;k$ : $x^2$ $+$ $2x$ $+$ $1$ $=$ $5k$
`x² + 2x + 1 = 5k` `( x + 1 ) ² = 5k` ⇒\(\left[ \begin{array}{l}x+ 1 =√5k ⇒x = √5k – 1\\x+1 = -√5k ⇒ x = -√5k – 1\end{array} \right.\) Bình luận
Tham khảo `x^2+2x+1=5k` `(x+1)^2=5k` `⇒(x+1)=\sqrt{±5k}` `⇒`\(\left[ \begin{array}{l}x=\sqrt{5k}-1\\x=\sqrt{-5k} -1\end{array} \right.\) Bình luận
`x² + 2x + 1 = 5k`
`( x + 1 ) ² = 5k`
⇒\(\left[ \begin{array}{l}x+ 1 =√5k ⇒x = √5k – 1\\x+1 = -√5k ⇒ x = -√5k – 1\end{array} \right.\)
Tham khảo
`x^2+2x+1=5k`
`(x+1)^2=5k`
`⇒(x+1)=\sqrt{±5k}`
`⇒`\(\left[ \begin{array}{l}x=\sqrt{5k}-1\\x=\sqrt{-5k} -1\end{array} \right.\)