Question

Find the nth term of the seqence -15,-5,5,15...

Answer 1

Answer

10n - 25

Given

nth terms of sequence = -15, -5, 5,15.......

Solution

First term = a = -15

Common Difference = d =

d = b - a = -5 - (-15) = 10

Nth term of ap = a + ( n-1) d

=> -15 + ( n-1 ) 10

=> -15 + 10n -10

=> 10n - 25 = Answer

Answer 2

10n + 25

Step-by-step explanation:

Given:-

A.P. :- -15, -5, 5, 15...

To find:-

• $\sf n^{th}$ term of sequence

Solution:-

First term of AP (a) = -15

Common difference (d) = -5 - (-15)

= 10

We know that,

$\:\:\star\;\sf \underline{ a_n = a + ( n - 1 )d}$

$:\implies\sf -15 + ( n - 1 ) 10 \\ \\ :\implies\sf -15 + 10n - 10 \\ \\ :\implies\bf {\underline{\blue{10n - 25}}}$

$\rule{200}{4}$