Question 11 and 12, Exercise 4.1

Solutions of Question 11 and 12 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.

Find the indicated term of the sequence: $a_{n}=4 n-3; a_8$.

Solution. Given $$a_n = 4n - 3.$$ Then \begin{align*} a_8 &= 4(8) - 3 \\ &= 32 - 3 \\ &= 29 \end{align*} Hence $a_8 = 29$. GOOD

Find the indicated term of the sequence. $a_{n}=5 n+11 ; a_{9}$

Solution.

Do yourself.