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13.

The equation x2+ax+b=0x^2 + ax + b = 0 and 2x2+ax+16=02x^2 + ax + 16 = 0 have one common root and if the other root of 2x2+ax+16=02x^2 + ax + 16 = 0 is 22, then find the values of aa and bb.

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Given the equations:

  1. x2+ax+b=0x^2 + ax + b = 0
  2. 2x2+ax+16=02x^2 + ax + 16 = 0

It is given that one of the roots of the equation 2x2+ax+16=02x^2 + ax + 16 = 0 is 22.
Substituting x=2x = 2 into 2x2+ax+16=02x^2 + ax + 16 = 0:
2(2)2+a(2)+16=02(2)^2 + a(2) + 16 = 0
8+2a+16=08 + 2a + 16 = 0
2a=−24  ⟹  a=−122a = -24 \implies a = -12

Now, the equation becomes:
2x2−12x+16=02x^2 - 12x + 16 = 0
x2−6x+8=0x^2 - 6x + 8 = 0
(x−2)(x−4)=0(x - 2)(x - 4) = 0
Thus, the roots of the second equation are x=2x = 2 and x=4x = 4.

Since the "other root" of this equation is 22, the common root between the two equations must be x=4x = 4.

Since x=4x = 4 is a root of x2+ax+b=0x^2 + ax + b = 0:
(4)2+a(4)+b=0(4)^2 + a(4) + b = 0
16+(−12)(4)+b=016 + (-12)(4) + b = 0
16−48+b=016 - 48 + b = 0
b−32=0  ⟹  b=32b - 32 = 0 \implies b = 32

Therefore, the required values are:
a=−12,b=32a = -12, \quad b = 32

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