Find the value of x satisfying log₃(x² - 4x + 3) = log₃(x - 1) — JEE Mathematics
Find the value of $x$ satisfying $\log_3(x^2 - 4x + 3) = \log_3(x - 1)$.
1 Answer
First, find the domain constraints for the logarithms to be defined:
- $x^2 - 4x + 3 > 0 \implies (x-1)(x-3) > 0 \implies x \in (-\infty, 1) \cup (3, \infty)$
- $x - 1 > 0 \implies x > 1$
Intersecting these two conditions gives the domain: $x > 3$.
Now equate the arguments:
$$x^2 - 4x + 3 = x - 1$$
$$x^2 - 5x + 4 = 0$$
$$(x - 1)(x - 4) = 0 \implies x = 1 or x = 4$$
Comparing with our domain condition ($x > 3$), $x = 1$ is excluded.
Therefore, $x = 4$.
Answer: 4