Question

2,4,8,16,.... aps progressions

Answer 1

t2 -t1 
= 4 - 2
= 2 --> first term
t3 - t2 
= 8 - 6 
= 2 --> second term
t4 - t3 
= 16 - 8 
= 8 --> third term

Answer 2

Answer:-

$\small\sf{a2-a1=4-2=2}$

$\small\sf{a3-a2=8-4=4}$

$\small\sf{a4-a3=16-8=8}$

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The difference between the successive terms are not same.

Hence,it is not an AP.