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Find the constants a and b such that x = -1 and x = 1 are both solutions to the equation ax^2 + bx + 2 = 0.

 Dec 22, 2021
 #1
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Input x=1. a + b + 2 = 0.

Input x = -1. a - b + 2 = 0.

Add the equations: 2a+4=0 --> a=-2

-2 + b + 2 = 0, so b = 0. 

 Dec 22, 2021
 #2
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Solutions are x = -1 and 1   means

(x+1)(x-1) = 0

x^2 +0x -1 = 0    multiply by -2 to get correct form

-2x^2 + 0x +2 = 0     a = -2      b= 0

 Dec 22, 2021

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