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Please help and Please write real equation for the answer thank you

Please help and Please write real equation for the answer thank you-example-1
User Ulrar
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1 Answer

6 votes

Answer:

f(x) = (3x -12)/(x² -7x +12)

Explanation:

The equation for a rational function can be written from the clues offered by the horizontal and vertical asymptotes, the y-intercept, and any "holes" in the function graph. Here, those clues are ...

  • horizontal asymptote: y = 0
  • vertical asymptote: x = 3
  • hole: (x, y) = (4, 3)
  • y-intercept: (0, -1)

__

The horizontal asymptote at y=0 tells you the denominator is of higher degree than the numerator. The vertical asymptote at x=3 tells you (x-3) is a factor of the denominator. The hole at x=4 tells you there is a factor of (x-4) in both numerator and denominator.

At this point, the function is tentatively ...


f(x)=a(x-4)/((x-3)(x-4))

Evaluating this at the y-intercept, x=0, gives ...

f(0) = -1 = a/(0 -3) = -a/3

a = 3 . . . . . multiply by -3

Then our rational function, consistent with all of the features of the graph, is ...


f(x)=(3(x -4))/((x -3)(x -4))\\\\\boxed{f(x)=(3x-12)/(x^2-7x+12)}

User Pierre Criulanscy
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3.9k points