Question

is 51 term of an ap 5,8,11,14

Answer 1

Here the first term; a = 5
Common difference; d = 11 - 8 = 8 - 5 = 3
So, nth term is given by;
tn = a+(n−1)d = 5+(n−1)×3
Now to prove whether 51 is term of this A.P, taking tn = 51
51 = 5+(n−1)×3
⇒51 = 5+3n−3
⇒3n = 51+3−5
⇒3n = 49 
n = 49/33
Now we know that number of terms can't be in fraction.
So, 51 is not term of this A.P.

hope this helps you....:)

Answer 2

HELLO DEAR,

GIVEN ,:-


given ap- 5,8,11,14....

a=5

d=3

an=51

an=a+(n-1)d

51= 5+ (n-1) 3

51= 5+3n-3

51-5=3n-3

46=3n-3

-3n+3=-46

-3n=-46-3

-3n=-49

n=-49/-3

n=49/3 which is not a whole number...hence we can conclude that 51 isnt a term of this ap