Question 206 Problem Solving 2018 GMAT Official Guide

Question 206 Problem Solving 2018 GMAT Official Guide

Video explanation: A sequence of numbers $a_1$, $a_2$, $a_3$,. . . defined as follows $a_1=3$…

Comments

Yousefsays

Can’t we just say that since a_n=t
then the terms before it namely a_n-1 and a_n-2 are 1 and t, as a result a_n would be t*1=t
then a_n+1 would be t*1*t=t^2
and thus a_n+2 would t*1*t*t^2 = t^4

Yousef says

Can’t we just say that since a_n=t

then the terms before it namely a_n-1 and a_n-2 are 1 and t, as a result a_n would be t*1=t

then a_n+1 would be t*1*t=t^2

and thus a_n+2 would t*1*t*t^2 = t^4

GMAT Quantum says

No, because $a_{n-1} = \sqrt{t}$ and $a_{n-2}= t^{\frac{1}{4}}$.