Question

Pls give explanation
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Answer 1

Solution:

Let p(x) = (5x+8)³-(a-x)³

If (x+1) is a factor of p(x) then

p(-1) = 0

=> [5(-1)+8]³-[a-(-1)]³ = 0

=> (-5+8)³ -(a+1)³ = 0

=> 3³-(a+1)³ = 0

=> (a+1)³ = 3³

=> a+1 = 3

=> a = 3-1

=> a = 2

=> a = 6/3

Therefore ,

Option (3) is correct.

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