Sovi.AI - AI Math Tutor

Scan to solve math questions

QUESTION IMAGE

explain the error in the work shown. find the correct answer. \\(\\frac…

Question

explain the error in the work shown. find the correct answer.
\\(\frac{1}{64} = 16^{2a}\\)
\\(4^{-3} = \left(2^4\
ight)^{2a}\\)
\\(4^{-3} = 2^{8a}\\)
\\(-3 = 8a\\)
\\(-\frac{3}{8} = a\\)

Explanation:

Step1: Identify the error

The original work incorrectly rewrote \(16\) as \(2^4\) when relating to \(4^{-3}\). Instead, \(16\) should be rewritten as \(4^2\) since we are working with a base of \(4\) on the left - hand side (\(4^{-3}\)). So the correct rewrite of \(16^{2a}\) is \((4^{2})^{2a}\), not \((2^{4})^{2a}\).

Step2: Rewrite the equation correctly

Starting from \(\frac{1}{64}=16^{2a}\), we know that \(\frac{1}{64} = 4^{-3}\) (because \(4^{3}=64\), so \(\frac{1}{64}=4^{-3}\)) and \(16 = 4^{2}\), so \(16^{2a}=(4^{2})^{2a}\).
Using the power - of - a - power rule \((x^{m})^{n}=x^{mn}\), we have \((4^{2})^{2a}=4^{4a}\).
So the correct equation is \(4^{-3}=4^{4a}\).

Step3: Solve for \(a\)

Since the bases are the same (\(4 = 4\)) and the equation \(4^{-3}=4^{4a}\) holds, we can set the exponents equal to each other (when \(x^{m}=x^{n}\), \(m = n\) for \(x
eq0,1, - 1\)).
So, \(-3 = 4a\).
To solve for \(a\), we divide both sides of the equation by \(4\): \(a=\frac{-3}{4}\).

Answer:

The error was in the base conversion (rewriting \(16^{2a}\) as \((2^{4})^{2a}\) instead of \((4^{2})^{2a}\)). The correct value of \(a\) is \(-\frac{3}{4}\).