Question

Find the first term and common difference in the A.P. $-\frac{1}{3},-\frac{1}{3},-\frac{1}{3},$ ........

• A. First term $=-\frac{1}{3}$; Common difference $=0$
• B. First term $=\frac{1}{3}$; Common difference $=1$
• C. First term $=\frac{2}{3}$; Common difference $=1$
• D. First term $=\frac{1}{3}$; Common difference $=2$

Answer 1

The correct option is A First term $=-\frac{1}{3}$; Common difference $=0$

Given series is $-\frac{1}{3},-\frac{1}{3},-\frac{1}{3},$ .....

Here first term is $-\frac{1}{3}$.

Common difference $a_2-a_1=a_3-a_2$

Here $a_1=-\frac{1}{3},a_2=-\frac{1}{3},a_3=-\frac{1}{3}$

Thus common difference $=-\frac{1}{3}+\frac{1}{3}=0$.