Practicing Success
Let $f(x) = \log_{x^2} 25$ and $g(x) = \log_x 5$. Then, $f(x) = g(x)$ holds for x belonging to |
R $\{x:0 < x < ∞, x≠1\}$ $\phi$ none of these |
$\{x:0 < x < ∞, x≠1\}$ |
The correct answer is Option (2) → $\{x:0 < x < ∞, x≠1\}$ We have, $f(x) =\log_{x^2} 25 = \log_{x^2}5^2=\frac{2}{2}\log_x5=\log_x5=g(x)$ for all x in their common domain. Now, $D_1$ = Domain of f = $R - \{0,-1, 1\}$ and, $D_2$ =Domain of g = $\{x: x > 0, x ≠ 1\}$ $∴D_1∩D_2 = \{x: x > 0, x ≠ 1\}$ Thus, $f (x) = g(x)$ for all $x ∈ \{x: x > 0, x≠ 1\}$ |