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Algebra

JEE Main level, single correct, medium

2 of 6

Question 2 of 6

The sum of the infinite geometric series $1 + \frac{1}{3} + \frac{1}{9} + \frac{1}{27} + \dots$ is:

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Answer: (B) $3/2$

S_\infty = \frac{a}{1 - r} = \frac{1}{1 - 1/3} = \frac{1}{2/3} = \frac{3}{2}

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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JEE Main Mathematics practice question on Algebra, with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

The sum of the infinite geometric series 1+13+19+127+…1 + \frac{1}{3} + \frac{1}{9} + \frac{1}{27} + \dots1+31​+91​+271​+… is:

JEE Main question paper PDF

More Mathematics practice

The sum of the infinite geometric series $1 + \frac{1}{3} + \frac{1}{9} + \frac{1}{27} + \dots$ is: