Question

(\(\dfrac{3}{4}\))^5*X=(\(\dfrac{3}{4}\))^7 hãy tìm X

Answer 1

\(\left(\dfrac{3}{4}\right)^5.x=\left(\dfrac{3}{4}\right)^7\)

\(\dfrac{3^5}{4^5}.x=\dfrac{3^7}{4^7}\)

\(x=\dfrac{3^7}{4^7}:\dfrac{3^5}{4^5}\)

\(x=\dfrac{3^7}{4^7}\).\(\dfrac{4^5}{3^5}\)

\(x=\dfrac{3^7.4^5}{4^7.3^5}\)

\(x=\dfrac{3^2}{4^2}=\dfrac{9}{16}\)

Answer 2

\(\left(\dfrac{3}{4}\right)^5.x=\left(\dfrac{3}{4}\right)^7\)

\(\Leftrightarrow x=\left(\dfrac{3}{4}\right)^7:\left(\dfrac{3}{4}\right)^5\)

\(\Leftrightarrow x=\left(\dfrac{3}{4}\right)^{7-5}\)

\(\Leftrightarrow x=\left(\dfrac{3}{4}\right)^2\)

\(\Leftrightarrow x=\dfrac{9}{16}\)

Vậy \(x=\dfrac{9}{16}\)

Answer 3

\(\left(\dfrac{3}{4}\right)^5\cdot x=\left(\dfrac{3}{4}\right)^7\)

\(\Rightarrow X=\left(\dfrac{3}{4}\right)^7:\left(\dfrac{3}{4}\right)^5\)

\(\Rightarrow X=\left(\dfrac{3}{4}\right)^{7-5}\)

\(\Rightarrow X=\left(\dfrac{3}{4}\right)^2=\dfrac{9}{16}\)