Sequences & Series · JEE Main previous year questions

2002 4 questions

1. Q172002 · 27 Apr 2002 · Shift 1

   If 1, ${\log }_9(3^{1-x}+2)$, ${\log }_3(4\cdot 3^x-1)$ are in A.P. then x equals

   1. A.${\log }_{3}4$
   2. B.$1-{\log }_{3}4$
   3. C.$1-{\log }_{4}3$
   4. D.${\log }_{4}3$
   Show answer

   Answer: B

2. Q182002 · 27 Apr 2002 · Shift 1

   l, m, n are the $p^{th}$, $q^{th}$ and $r^{th}$ term of a G.P all positive, then $\left|\begin{array}{ccc}\log l& p& 1\\ \log m& q& 1\\ \log n& r& 1\end{array}\right|$ equals

   1. A.$-1$
   2. B.$2$
   3. C.$1$
   4. D.$0$
   Show answer

   Answer: D

3. Q192002 · 27 Apr 2002 · Shift 1

   Fifth term of a GP is 2, then the product of its first 9 terms is

   1. A.256
   2. B.512
   3. C.1024
   4. D.none of these
   Show answer

   Answer: B

4. Q202002 · 27 Apr 2002 · Shift 1

   Sum of infinite number of terms of GP is 20 and sum of their square is 100. The common ratio of GP is

   1. A.5
   2. B.3/5
   3. C.8/5
   4. D.1/5
   Show answer

   Answer: B