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AP EAMCET20226 Jul 2022Morning ShiftMathematicsFunctionsActual

If f(x)=a x^2+b x+c satisfies f(1)+2 f(2)=0 and 2 f (1)+ f (2)=0 , then 3 a + b =

Options

  1. A2
  2. B-1
  3. C0
  4. D1

Correct answer

C. 0

Step-by-step solution

f(x)=a x^2+b x+c (Given) f (1)= a + b + c 2 f (2)=2(4 a +2 ~b + c ) since f(1)+f(2)=0 9 a +5 ~b +3 c =0...(i) similarly 6 a+4 b+3 c=0...(ii) now subtracting (ii) from (i) we get 3 a+b=0

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