Solve the given equation ((log_{3} x)^{2} – 6(log_{3} x) + 9 = 0)

Solve the given equation ((log_{3} x)^{2} – 6(log_{3} x) + 9 = 0)

  • A.
    27
  • B.
    9
  • C.
    (frac{1}{27})
  • D.
    18
  • E.
    81
Correct Answer: Option A
Explanation

((log_{3} x)^{2} – 6(log_{3} x) + 9 = 0)

Let (log_{3} x = a).

(a^{2} – 6a + 9 = 0)

(a^{2} – 3a – 3a + 9 = 0)

(a(a – 3) – 3(a – 3) = 0)

((a – 3)(a – 3) = 0)

(implies a = 3 (twice))

(log_{3} x = 3 implies x = 3^{3} = 27)

You May Also Like