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The value of m such that (2/9)^3xx(4/81)...

The value of m such that `(2/9)^3xx(4/81)^(-6)=(2/9)^(2m-1)` is

A

-6

B

0

C

-4

D

3

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \((\frac{2}{9})^3 \times (\frac{4}{81})^{-6} = (\frac{2}{9})^{2m-1}\), we will follow these steps: ### Step 1: Simplify \((\frac{4}{81})^{-6}\) First, we can rewrite \(\frac{4}{81}\) in terms of \(\frac{2}{9}\): \[ \frac{4}{81} = \frac{2^2}{(3^4)} = \left(\frac{2}{9}\right)^{2} \text{ (since } 81 = 9^2 \text{)} \] Thus, \[ (\frac{4}{81})^{-6} = \left(\left(\frac{2}{9}\right)^{2}\right)^{-6} = \left(\frac{2}{9}\right)^{-12} \] ### Step 2: Substitute back into the equation Now we can substitute this back into the original equation: \[ (\frac{2}{9})^3 \times (\frac{2}{9})^{-12} = (\frac{2}{9})^{2m-1} \] ### Step 3: Combine the exponents on the left side Using the property of exponents \(a^m \times a^n = a^{m+n}\): \[ (\frac{2}{9})^{3 + (-12)} = (\frac{2}{9})^{2m-1} \] This simplifies to: \[ (\frac{2}{9})^{-9} = (\frac{2}{9})^{2m-1} \] ### Step 4: Set the exponents equal to each other Since the bases are the same, we can set the exponents equal to each other: \[ -9 = 2m - 1 \] ### Step 5: Solve for \(m\) Now, we will solve for \(m\): \[ 2m = -9 + 1 \] \[ 2m = -8 \] \[ m = -4 \] ### Final Answer Thus, the value of \(m\) is: \[ \boxed{-4} \]
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