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Find the nth term of an arithmetic progression whose . . .

Question : Find the nth term of an arithmetic progression whose first term is 7 and the 6th term of the AP exceeds its 2nd term by 16.


Doubt by Riddhi

Solution :

a = 7 (Given)
a6-a2=16
We know, 
an=a+(n-1)d
a6=a+(6-1)d
a6=a+5d

similarly 
a2=a+d

a6-a2=16
a+5d-(a+d)=16
a+5d-a-d=16
a-a+5d-d=16
0+4d=16
4d=16
d=16/4
d=4

Now, 
an=a+(n-1)d
an=7+(n-1)4
an=7+4n-4
an=3+4n
an=4n+3

Hence, the required nth term of the AP is 4n+3.