Question

Find the first four terms of an AP, whose first term is $-\frac{1}{2}$ and the common difference is $-1$.

Answer 1

Find the first four terms of an AP:

Here, the first term $a_1=-\frac{1}{2}$ and common difference $d=-1$.

$\Rightarrow a_1=\frac{-1}{2}$

$\begin{array}{rcl}& \Rightarrow & a_2=a_1+d\\ & =& -\frac{1}{2}-1\\ & =& -\frac{3}{2}\end{array}$

$\begin{array}{rcl}& \Rightarrow & a_3=a_2+d\\ & =& -\frac{3}{2}-1\\ & =& -\frac{5}{2}\end{array}$

$\begin{array}{rcl}& \Rightarrow & a_4=a_3+d\\ & =& -\frac{5}{2}-1\\ & =& -\frac{7}{2}\end{array}$

Hence, the first four terms of AP is $\frac{-1}{2},\frac{-3}{2},\frac{-5}{2},\frac{-7}{2}$.