Question 28

Which of the given options is the pattern of the sequence 1, 5, 11, 19, 29 ?

Solution

$$1+2^2=5   x^2 + (x-1)$$
$$2+3^2=11=x^2 + (x-1)$$
$$3+4^2=19=x^2 + (x-1)$$
$$4+5^2=29=x^2 + (x-1)$$
$$5+6^2=41=x^2 + (x-1)$$
$$6+7^2=55=x^2 + (x-1)$$

from this we concluded that 

$$x^2 + x - 1$$


Create a FREE account and get:

  • Download RRB Study Material PDF
  • 45+ RRB previous papers with solutions PDF
  • 300+ Online RRB Tests for Free

cracku

Boost your Prep!

Download App