A geometric series has first term and common ratio . What is its sum to infinity?
Answer and explanation
Correct answer: D. 18
- Step 1: For , . Step 2. . Answer: 18. Why not the others: a/r gives 36; a/(1+r) gives 9 or 16 type errors; dividing by 3 only gives 4.
Practise more Calculus, Complex Numbers, Vectors and Probability.
Free questions with an explanation for every one, and full timed Wazari Exam (Iraq Baccalaureate) - Scientific Branch mock tests.