Question 903117
(3 b ^ -4 ) ^ 2 
=  (3)^2 * ( b ^ -4 ) ^ 2
=  9 * b ^ -8
=  9/ b ^8

x ^ 4b + 2 ( x ^ 5b)
= x ^ 4b  +  2 x ^ 5b
= x ^ 4b ( 1+ 2 x ^ b) 
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