If
let g(x) = x + 2a and p(x) = x5 – 4a2x3 + 2x + 2a + 3
Putting g(x) = 0
⟹ x + 2a = 0 ⟹ x = – 2a
According to the factor theorem if g(x) is a factor of p(x) then p( – 2a) = 0
Now p ( – 2a) = ( – 2a)5 – 4a2( – 2a)3 + 2( – 2a) + 2a + 3 = 0
⟹ – 32a5 + 32a5 – 2a + 3 = 0 ⟹ – 2a = – 3
⟹ 
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