Question

The general term of ap is2n+5 them it's common difference

Answer 1

The nth term of an A.P. is (3n+5). What is the seventh term?
nth term is equal to. a+(n-1)d

a+(n-1)d= 3n + 5

On opening bracket on l.h.s.

dn + (a-d)= 3n + 5.

On comparing both the sides.

dn= 3n therefore d=3.

Also a-d = 5

a-3 =5

a= 8

Seventh term = 8+ (7–1)×3

Seventh term = 8+18

The answer is 26.

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