Substitution to Transform Integral Form (Show Transformed Expression)
The question provides a specific substitution and asks the student to show or identify the resulting transformed integral without necessarily evaluating it to a final numerical answer.
Consider the function $$f(x) = \frac{\sin x}{3 - 2\cos x} \quad (0 \leqq x \leqq \pi)$$ (1) The derivative of $f(x)$ is $$f'(x) = \frac{\mathbf{A}\cos x - \mathbf{B}}{(\mathbf{C} - \mathbf{D}\cos x)^2}.$$ Let $\alpha$ be the value of $x$ at which $f(x)$ has a local extremum. Then we have $$\cos\alpha = \frac{\mathbf{E}}{\mathbf{F}}.$$ (2) The portion of the plane bounded by the graph of the function $y = f(x)$ and the $x$-axis is divided into two parts by the straight line $x = \alpha$. Let $S_1$ be the area of the part located on the left side of the line. Then we have $$S_1 = \int_{\frac{\mathbf{G}}{\mathbf{H}}}^{\mathbf{I}} \frac{dt}{\mathbf{J} - \mathbf{K}t} = \frac{\mathbf{L}}{\mathbf{L}}\log\frac{\mathbf{L}}{\mathbf{L}}.$$ Let $S_2$ be the area of the part located on the right side. We have $$S_2 = \frac{\mathbf{P}}{2}\log\mathbf{Q}.$$
In the integral $\int \frac { \ln \sqrt { x } } { \sqrt { x } } d x$, if the substitution $u = \sqrt { x }$ is made, which of the following integrals is obtained? A) $\int \ln u \, d u$ B) $\int 2 \ln u \, d u$ C) $\int \frac { \ln u } { u } d u$ D) $\int \frac { \ln u } { 2 u } d u$ E) $\int u \ln u \, d u$
$\int \sqrt { 1 + e^{x^{2}} } \, d x$\ In the integral, if the substitution $u = \sqrt { 1 + e ^ { x } }$ is made, which of the following integrals is obtained?\ A) $\int \frac { 2 u } { u ^ { 2 } + 1 } d u$\ B) $\int \frac { u ^ { 2 } } { u ^ { 2 } + 1 } d u$\ C) $\int \frac { 1 } { u ^ { 2 } - 1 } d u$\ D) $\int \frac { u } { u ^ { 2 } - 1 } d u$\ E) $\int \frac { 2 u ^ { 2 } } { u ^ { 2 } - 1 } d u$