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Given that (f : x to frac{2x – 1}{x + 2}, x neq -2), find…

Given that (f : x to frac{2x – 1}{x + 2}, x neq -2), find (f^{-1}), the inverse of f.

  • A.
    (f^{-1} : x to frac{1+2x}{2-x}, x neq 2)
  • B.
    (f^{-1} : x to frac{1-2x}{x+2}, x neq -2)
  • C.
    (f^{-1} : x to frac{1-2x}{x-2}, x neq 2)
  • D.
    (f^{-1} : x to frac{1+2x}{x+2}, x neq -2)
Correct Answer: Option A
Explanation

(f(x) = frac{2x – 1}{x + 2})

(y = frac{2x – 1}{x + 2})

(x = frac{2y – 1}{y + 2} implies x(y + 2) = 2y – 1)

(xy – 2y = -1 – 2x  implies y = frac{-1 – 2x}{x – 2})

(f^{-1} : x to frac{1 + 2x}{2 – x} ; x neq 2)