\(\left(\frac{1}{3}-1,35x\right)^4=\frac{625}{256}\)
\(\left(\frac{1}{3}-1,35x\right)^4=\left(\frac{5}{4}\right)^4\)
\(\Rightarrow\frac{1}{3}-1,35x=\frac{5}{4}\)
\(1,35x=\frac{1}{3}-\frac{5}{4}\)
\(1,35x=\frac{-11}{12}\)
\(x=\frac{-11}{12}:1,35\)
\(x=\frac{-55}{81}\)
\(\left(\frac{1}{3}-1,35x\right)^4=\frac{625}{256}\)
\(\left(\frac{1}{3}-\frac{27}{20}\cdot x\right)^4=\frac{625}{256}\)
\(\left(\frac{1}{3}-\frac{27}{20}\cdot x\right)^4=\left(\frac{5}{4}\right)^4\)
\(\Rightarrow\left(\frac{1}{3}-\frac{27}{20}\cdot x\right)=\left(\frac{5}{4}\right)^4\)vì \(\left(\frac{5}{4}\right)^4=\frac{625}{256}\)
còn lại bạn tự tính nhé
