Question

please help me to solve this I need to know how to find the numbers in the place of A and B
reply fast because tomorrow is my exam of this subject.

Answer 1

$3 = 2 + {2}^{0} \\ 5 = 3 + 2 {}^{1} \\ 9 = 5 + {2}^{2} \\ 17 = 9 + 2^{3} \\ a = 17 + 2^{4} = 17 + 16 = 33 \\ 65 = 33 + 2^{5} \\ b = 65 + {2}^{6} = 129$