giúp mik câu này với
x2 + 1; \(\dfrac{x^4}{x^2-1}\)
X I N C Ả M Ơ N
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Quy đồng :
\(\dfrac{1}{2}\) = \(\dfrac{\text{1 × 30}}{\text{2 × 30 }}\) = \(\dfrac{30}{60}\)
\(\dfrac{2}{3}\) = \(\dfrac{\text{2 × 20}}{\text{3 × 20 }}\) = \(\dfrac{40}{60}\)
\(\dfrac{3}{4}\) = \(\dfrac{\text{3 × 15 }}{4×15}\) = \(\dfrac{45}{60}\)
\(\dfrac{4}{5}\) =\(\dfrac{\text{4 × 12 }}{5×12}\) = \(\dfrac{48}{60}\)
\(\dfrac{5}{6}\) = \(\dfrac{\text{5 × 10 }}{6×10}\) = \(\dfrac{50}{60}\)
⇒ 30 < 40 < 45 < 48 < 50
\(\dfrac{1}{2}\) < \(\dfrac{2}{3}\) < \(\dfrac{3}{4}\) < \(\dfrac{4}{5}\) < \(\dfrac{5}{6}\)
\(\dfrac{1}{2}\) ; \(\dfrac{2}{3}\) ; \(\dfrac{3}{4}\) ; \(\dfrac{4}{5}\) ; \(\dfrac{5}{6}\)
Ta có: \(3,2-x=1\frac13\)
=>\(\frac{16}{5}-x=\frac43\)
=>\(x=\frac{16}{5}-\frac43=\frac{48-20}{15}=\frac{28}{15}\)
`@` `\text {Ans}`
`\downarrow`
\(\left(\dfrac{1}{5}\right)^{2x-1}=\dfrac{1}{125}\)
`=>`\(\left(\dfrac{1}{5}\right)^{2x-1}=\left(\dfrac{1}{5}\right)^3\)
`=>`\(2x-1=3\)
`=> 2x = 3 + 1`
`=> 2x = 4`
`=> x = 4 \div 2`
`=> x = 2`
Vậy, `x = 2.`
`@` `\text {Kaizuu lv uuu}`
1. Why don't you play with her?
2. Is the maid cleaning the floor?
Ta có: \(\left(\dfrac{4}{7}-\dfrac{1}{3}\right)^x=8\)
\(\Leftrightarrow\left(\dfrac{5}{21}\right)^x=8\)
\(\dfrac{1}{2}\left(x-2\right)+\dfrac{1}{3}\left(2-x\right)=x\\ \Leftrightarrow\dfrac{1}{2}\left(x-2\right)-\dfrac{1}{3}\left(x-2\right)=x\\ \Leftrightarrow\left(x-2\right).\left(\dfrac{1}{2}-\dfrac{1}{3}\right)=x\\ \Leftrightarrow\left(x-2\right).\left(\dfrac{3-2}{6}\right)=x\\ \Leftrightarrow\left(x-2\right).\dfrac{1}{6}=x\\ \Leftrightarrow\dfrac{1}{6}x-\dfrac{1}{3}-x=0\\ \Leftrightarrow\left(\dfrac{1}{6}-1\right)x=\dfrac{1}{3}\\ \Leftrightarrow\left(\dfrac{1-6}{6}\right)x=\dfrac{1}{3}\\ \Leftrightarrow\dfrac{-5}{6}x=\dfrac{1}{3}\\ \Leftrightarrow x=\dfrac{1}{3}:\left(-\dfrac{5}{6}\right)\\ \Leftrightarrow x=-\dfrac{2}{5}\)
Vậy \(x=-\dfrac{2}{5}\)

\(x^2+1=\dfrac{x^4-1}{x^2-1}\)