The sum of the real roots of the equation x - 6 - 1 2 - 3 x x - 3 - 3 2 x x + 2 = 0 , is equal to:

The sum of the real roots of the equation
x-6-12-3xx-3-32xx+2=0, is equal to:
  1. 0
  2. -4
  3. 6
  4. 1

Solution

Given x-6-12-3xx-3-32xx+2=0

On expansion, we get x-3xx+2-2xx-3+62x+2+3x-3-14x-9x=0

x-3x2-6x-2x2+6x+62x+4+3x-9-1-5x=0

-5x3+30x-30+5x=0

5x3-35x+30=0

x3-7x+6=0

x-1x-2x+3

x=1 or x=2 or x=-3.

Here all roots 1, 2, -3 are real, hence the sum of the real roots is 1+2-3=0.

Asked in: JEE Main 2019 (10 Apr Shift 2)

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