Geometric Progression With Logarithms
If positive numbers x, y, z are in geometric progression, then the logarithms log x, log y, log z to a common base form which kind of progression?
Select the correct option:
🔒 Solution Hidden from View
Submit your answer to unlock the detailed step-by-step solution.
More sequence and series Practice Questions
If the numbers a, b, c are simultaneously in arithmetic progression and in geometric progression wit...
If the numbers a, b, c are simultaneously in arithmetic progression and in geometric progression wit...
The general term of a series is given by T_k = k(k+2); evaluate the sum of the first n terms of this...
The general term of a series is given by T_k = k(k+2); evaluate the sum of the first n terms of this...
The sum of the first n terms of a certain sequence equals S_n = 3n^2 + 5n for every positive integer...
The sum of the first n terms of a certain sequence equals S_n = 3n^2 + 5n for every positive integer...
Assertion: the series with terms 1/n diverges; Reason: every series whose terms tend to zero must co...
Assertion: the series with terms 1/n diverges; Reason: every series whose terms tend to zero must co...
Determine the exact value of the convergent infinite sum whose kth term is k/2^k, taken over all pos...
Determine the exact value of the convergent infinite sum whose kth term is k/2^k, taken over all pos...
Determine the sum to \infty of the arithmetico-geometric series 1 + 2x + 3x^2 + 4x^3 + ... when the...
Determine the sum to \infty of the arithmetico-geometric series 1 + 2x + 3x^2 + 4x^3 + ... when the...
Three numbers are in geometric progression, their product equals 216, and the sum of the outer two n...
Three numbers are in geometric progression, their product equals 216, and the sum of the outer two n...
For two distinct positive numbers, their arithmetic mean is 10 and their geometric mean is 8; comput...
For two distinct positive numbers, their arithmetic mean is 10 and their geometric mean is 8; comput...
Find the sum of the telescoping series whose general term is 1/(k(k+1)) summed from k equal to 1 up ...
Find the sum of the telescoping series whose general term is 1/(k(k+1)) summed from k equal to 1 up ...
A worker is paid 200 rupees in the first month and receives an increment of 25 rupees each subsequen...
A worker is paid 200 rupees in the first month and receives an increment of 25 rupees each subsequen...
Express the recurring decimal 0.overline{36}, meaning 0.363636 repeating endlessly, as a fully reduc...
Express the recurring decimal 0.overline{36}, meaning 0.363636 repeating endlessly, as a fully reduc...
Consider the infinite geometric series 9 - 6 + 4 - 8/3 + ... that converges; what is its exact sum t...
Consider the infinite geometric series 9 - 6 + 4 - 8/3 + ... that converges; what is its exact sum t...
About This Question
- Subject
- mathematics
- Chapter
- sequence and series
- Topic
- geometric progression with logarithms
- Difficulty
- Hard
- Year
- 2025
Solution
Correct Answer:
Arithmetic progression
This question links progressions through the logarithm's transformation of products into sums, a connection JEE Advanced uses to convert multiplicative structure into additive structure. Since x, y, z are in GP, the middle term satisfies y^2 = xz. Taking logarithms of both sides gives 2 log y = log x + log z, which is precisely the defining condition for log x, log y, log z to be in arithmetic progression. Thus the logarithms form an AP. Option geometric progression is wrong because logarithms convert the constant ratio into a constant difference, not a ratio. Option harmonic progression has no basis here, since reciprocals of logarithms are not forced to be arithmetic. Option no fixed progression contradicts the clean derived condition. Hence the answer is arithmetic progression. This duality runs both ways: applying the exponential function, the inverse of the logarithm, turns an arithmetic progression of exponents back into a geometric progression of values, so logarithms and exponentials act as a translation dictionary between additive and multiplicative structure, a theme JEE Advanced returns to repeatedly. Plausibility check: for the GP 1, 10, 100 in base ten the logarithms are 0, 1, 2, which are equally spaced and therefore arithmetic, directly confirming the general result.
This hard difficulty mathematics question is from the chapter sequence and series, covering the topic of geometric progression with logarithms. It appeared in the 2025 exam.
Looking for more practice? Explore all mathematics questions or browse sequence and series questions on RankGuru.