Find the value of a and bif x-1 and x-2 are factors of x-ax+b.​

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1. Correct question:

   Find the value of a and bif x-1 and x-2 are factors of x³-ax+b.

   Solution:

   As x-1 and x-2 are factors of the expression,

   x – 1 = 0 and x – 2 = 0 will be its zeroes.

   x = 1 and x = 2 are the zeroes of the expression,

   Therefore,

   1³ – a×1 + b = 0

   => -a + b = -1 —(1)

   And,

   2³ – a×2 + b = 0

   => – 2a + b = – 8 —(2)

   Subtract 2 from 1

   -a -(-2a) + b – b = -1 -(-8)

   => a = 8 – 1 = 7

   a = 8 – 1 = 7b = -1 + a = 6

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