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NDA2018MathematicsContinuity and DifferentiabilityActual

If f(x)= x^2-9 x^2-2 x-3 , x 3 is continuous at x=3 , then which one of the following is correct?

Options

  1. Af(3)=0
  2. Bf(3)=1.5
  3. Cf(3)=1.5
  4. Df(3)=-1.5

Correct answer

B. f(3)=1.5

Step-by-step solution

f(x)= x^2-9 x^2-2 x-3 Given, the function is continuous at x =3 . aligned & f(3)= _ x 3 x^2-9 x^2-2 x-3 & = _ x 3 (x+3)(x-3) (x-3)(x+1) & = 3+3 3+1 = 6 4 = 3 2 =1.5 aligned

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