lỗi mik nhầm \(\frac{-8}{27}\)thành \(\frac{-25}{9}\)nhé
a.\(\left(x+\frac{2}{3}\right)^2=\frac{25}{9}\)
\(\left(x+\frac{2}{3}\right)^2=\frac{5^2}{3^2}\)
\(\left(x+\frac{2}{3}\right)^2=\left(\frac{5}{3}\right)^2\)
\(\Rightarrow x+\frac{2}{3}=\frac{5}{3}\)
\(x=\frac{5}{3}-\frac{2}{3}\)
\(x=\frac{3}{3}\)
\(x=1\)
cau b ne ban
\(\left(2x-\frac{1}{2}\right)^3=\frac{-8}{27}\)
\(\left(2x-\frac{1}{2}\right)^3=\frac{-2^3}{3^3}\)
\(\left(2x-\frac{1}{2}\right)^3=\left(\frac{-2}{3}\right)^3\)
\(\Rightarrow2x-\frac{1}{2}=\frac{-2}{3}\)
\(2x=\frac{-2}{3}+\frac{1}{2}\)
\(2x=\frac{-4}{6}-\frac{3}{6}\)
\(2x=\frac{-7}{6}\)
\(x=\frac{-7}{6}\div2\)
\(x=\frac{-7}{6}\times\frac{1}{2}\)
\(x=\frac{-7}{12}\)
Oky roi do ban :)))
