Proof of Given Relation
Question
\[
2^x = 3^y = 6^{-z}
\]
Solution
Let \(2^x = 3^y = 6^{-z} = k\)
\[
x = \log_2 k,\quad y = \log_3 k,\quad -z = \log_6 k
\]
\[
\frac{1}{x} = \log_k 2,\quad \frac{1}{y} = \log_k 3,\quad \frac{1}{z} = -\log_k 6
\]
\[
\frac{1}{x} + \frac{1}{y} + \frac{1}{z}
= \log_k 2 + \log_k 3 – \log_k 6
\]
\[
= \log_k (2 \cdot 3) – \log_k 6
\]
\[
= \log_k 6 – \log_k 6
\]
\[
= 0
\]
Answer
\[
\boxed{0}
\]
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