The area bounded by the curve $y=\ln (x)$ and the lines $y=0, y=\ln (3)$ and $x=0$ is equal to:
The area bounded by the curve $y=\ln (x)$ and the lines $y=0, y=\ln (3)$ and $x=0$ is equal to:
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3
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$3 \ln (3)-2$
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$3 \ln (3)+2$
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2
Solution
To find the point of intersection of curves
$
\begin{aligned}
& y=\ln (x) \text { and } y=\ln (3), \text { put } \ln (x)=\ln (3) \\
\Rightarrow & \ln (x)-\ln (3)=0 \\
\Rightarrow & \ln (x)-\ln (3)=\ln (1) \\
\Rightarrow & \frac{x}{3}=1, \Rightarrow x=3
\end{aligned}
$

$\begin{aligned} \text { Required area } & =\int_0^3 \ln (3) d x-\int_1^3 \ln (x) d x \\ = & {[x \ln (3)]_0^3-\left[x \ln (x)-x_1^3=2\right.}\end{aligned}$
Asked in: JEE Main 2013 (09 Apr Online)
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