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Find a and b if x4+3x3−2x2+ax+b is divisible by (x2–3x+2)

User Atazmin
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1 Answer

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First factor x² - 3x + 2 → (x - 1) (x - 2) Set each factor equal to zero and solve: x = 1 and x = 2Plug each value into the dividend, This will create two linear equations you can solve using elimination.x = 1 → (1)^4 + 3(1)³- 2(1)² + a(1) + b = 0 → 2 + a + b = 0 → a + b = -2x = 2 → (2)^4 + 3(2)³- 2(2)² + a(2) + b = 0 → 32 + 2a + b = 0 → 2a + b = -32
Subtract the equations: 2a + b = -32- a - b = -(-2)------------------a = -30 → a + b = -2 → -30 + b = -2 → b = 28Answer: a = -30 and b = 28

User Walter Underwood
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