====== 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. 


=====Question 11=====
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

=====Question 12=====
Find the indicated term of the sequence. $a_{n}=5 n+11 ; a_{9}$

** Solution. **

Do yourself.



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