Q12 of 96 Page 6

Find the value of a, if x+2 is a factor of 4x4+2x3-3x2+8x+5a.

Let, f (x) = 4x4+2x3-3x2+8x+5a

f (-2) = 0


4 (-2)4 + 2 (-2)3 – 3 (-2)2 + 8 (-2) + 5a = 0


64 – 16 – 12 – 16 + 5a = 0


5a = - 20


a = -4


Hence, (x + 2) is a factor f (x) when a = -4.


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