If x+1,3x and 4x+2 are the first three terms of an AP, then its 5th term is ___.
24
Given, x+1,3x,4x+2 are in AP.
So, the difference of any two consecutive terms will be the same.
∴3x–(x+1)=(4x+2)–3x
⇒ 2x−1=x+2
⇒ x=3
So, the first term of the AP is a=x+1=3+1=4.
The second term of the AP is 3x=3×3=9.
∴Common difference, d=9–4=5
The nth term of an AP with first term a and common difference d is given by
tn=a+(n−1)d.
⇒t5=4+4(5)=24