Question

if nth term of an ap is an=5n-2 then a12

Answer 1

An=5n-2
First term,a=5×1-2=3
second term,a2=5×2-2=8
d=a2-a1=8-3=5
12th term=5×12-2=60-2=58

Answer 2

The 12th term of an AP, $a_{12}$=80

Step-by-step explanation:

Given,

The nth term of an Ap, $a_{n} =$ 5n - 2

To find, the 12th term of an AP, $a_{12}=?$

Put n = 1 , 2, 3, 4, ......., n

The 1st term of an AP,

$a_{1} =$ 5(1) - 2  = 5 - 2 = 3

The 2nd term of an AP,

$a_{2}=$ 5(2) - 2  = 10 - 2 = 8

The 3rd term of an AP,

$a_{3}=$5(3) - 2  = 15 - 2 = 13

....

The 12th term of an AP,

$a_{12}=$5(12) - 2  = 60 - 2 = 58

Hence, the 12th term of an AP,$a_{12}$=80