If \( \Large 3^{x}=5^{y}=45^{z} \), then


A) \( \Large x+y+z=0 \)

B) \( \Large \frac{2}{x}=\frac{1}{z}-\frac{1}{y} \)

C) \( \Large \frac{2}{y}=\frac{1}{x}-\frac{1}{z} \)

D) \( \Large \frac{2}{z}=\frac{1}{y}-\frac{1}{x} \)

Correct Answer:
B) \( \Large \frac{2}{x}=\frac{1}{z}-\frac{1}{y} \)

Description for Correct answer:

Let \( \Large 3^{x} = 5^{y} = 45^{z} = k \)

=> \( \Large 3=k^{\frac{1}{x}},\ 5=k^{\frac{1}{y}},\ and\ 45=k^{\frac{1}{z}} \)

Now \( \Large \left(3^{2} \times 5\right) = k^{\frac{1}{z}} \)

=> \( \Large \left(k^{\frac{1}{x}}\right)^{2} \times k^{\frac{1}{y}} = k^{\frac{1}{z}} \)

=> \( \Large \frac{2}{x}+\frac{1}{y}=\frac{1}{z} \)

\( \Large \therefore \frac{2}{x}=\frac{1}{z}-\frac{1}{y} \)


Part of solved Polynomials questions and answers : >> Elementary Mathematics >> Polynomials








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