Q55.If the sum of the first 20 terms of the series log(71/2) x + log(71/3) x + log(71/4) x + … is 460 , then x is equal to: (1) 72 (2) 71/2 (3) e2 (4) 746/21
What This Question Tests
This question tests the application of logarithm properties to transform a series into an arithmetic progression, calculate its sum, and then solve for the unknown variable x.
Concepts Tested
Formulas Used
log_b a = (log a) / (log b)
log(m^n) = n log m
Sn = n/2 * (2a + (n-1)d)
📚 NCERT Sections This Tests
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
3.20 — For The Decomposition Of Azoisopropane To Hexane And Nitrogen At 543
Chemistry Class 11 · Chapter 3
3.20 For the decomposition of azoisopropane to hexane and nitrogen at 543 K, the following data are obtained. t (sec) P(mm of Hg) 0 35.0 360 54.0 720 63.0 Calculate the rate constant.
📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Logarithmic series and AP
- Year
- 2020
- Shift
- 05 Sep Shift 2
- Q Number
- Q55
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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