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For $$x \gt 1$$, if $$(2x)^{2y} = 4e^{2x-2y}$$, then $$(1 + \log_e 2x)^2 \frac{dy}{dx}$$ is equal to
We are given the functional relation for $$x \gt 1$$
$$ (2x)^{2y}=4\,e^{\,2x-2y}. $$
First take the natural logarithm (base $$e$$) of both sides. Using the law $$\ln a^{b}=b\ln a,$$ we obtain
$$ \ln\!\bigl((2x)^{2y}\bigr)=\ln\!\bigl(4e^{\,2x-2y}\bigr). $$
Thus
$$ 2y\,\ln(2x)=\ln 4 + 2x-2y. $$
We now differentiate implicitly with respect to $$x$$. Remember that $$y=y(x)$$ is a function of $$x$$, so whenever $$y$$ is differentiated we must multiply by $$\dfrac{dy}{dx}$$ (the chain rule).
Derivative of the left side:
$$ \dfrac{d}{dx}\!\bigl[2y\,\ln(2x)\bigr]=2\frac{dy}{dx}\,\ln(2x)+2y\cdot\dfrac{d}{dx}\!\bigl[\ln(2x)\bigr]. $$
Since $$\dfrac{d}{dx}\bigl[\ln(2x)\bigr]=\dfrac{1}{2x}\cdot 2=\dfrac{1}{x},$$ the left derivative becomes
$$ 2\frac{dy}{dx}\,\ln(2x)+\dfrac{2y}{x}. $$
Derivative of the right side:
$$ \dfrac{d}{dx}\!\bigl[\ln 4 + 2x-2y\bigr]=0+2-2\frac{dy}{dx}. $$
Equating the two derivatives, we have
$$ 2\frac{dy}{dx}\,\ln(2x)+\dfrac{2y}{x}=2-2\frac{dy}{dx}. $$
Gathering the $$\dfrac{dy}{dx}$$ terms on one side:
$$ 2\frac{dy}{dx}\,\ln(2x)+2\frac{dy}{dx}=2-\dfrac{2y}{x}. $$
Factor out $$2\dfrac{dy}{dx}$$:
$$ 2\frac{dy}{dx}\,\bigl(\ln(2x)+1\bigr)=2-\dfrac{2y}{x}. $$
Divide by $$2\bigl(\ln(2x)+1\bigr)$$ to get
$$ \frac{dy}{dx}= \frac{1-\dfrac{y}{x}}{\ln(2x)+1}. $$
Because we ultimately need $$(1+\ln 2x)^2\dfrac{dy}{dx},$$ we next express $$y$$ explicitly in terms of $$x$$. Returning to the original logarithmic equation
$$ 2y\,\ln(2x)+2y=\ln 4+2x, $$
or equivalently
$$ 2y\bigl(\ln(2x)+1\bigr)=\ln 4+2x. $$
Hence
$$ y=\frac{\ln 4+2x}{2\bigl(\ln(2x)+1\bigr)}. $$
Now compute $$1-\dfrac{y}{x}$$:
$$ 1-\frac{y}{x}=1-\frac{\ln 4+2x}{2x\bigl(\ln(2x)+1\bigr)} =\frac{2x\bigl(\ln(2x)+1\bigr)-\bigl(\ln 4+2x\bigr)} {2x\bigl(\ln(2x)+1\bigr)} =\frac{2x\ln(2x)-\ln 4}{2x\bigl(\ln(2x)+1\bigr)}. $$
Therefore
$$ (1+\ln 2x)^2\frac{dy}{dx} =(1+\ln 2x)\Bigl(1-\frac{y}{x}\Bigr) =(1+\ln 2x)\, \frac{2x\ln(2x)-\ln 4}{2x\bigl(\ln(2x)+1\bigr)} =\frac{2x\ln(2x)-\ln 4}{2x}. $$
The factor $$1+\ln 2x$$ in numerator and denominator cancels neatly, leaving
$$ (1+\ln 2x)^2\frac{dy}{dx} =\frac{2x\ln(2x)-\ln 4}{2x} =\ln(2x)-\frac{\ln 2}{x}. $$
Since $$\ln 4=2\ln 2,$$ the final form may be written as
$$ \frac{x\,\ln(2x)-\ln 2}{x}, $$
which coincides exactly with Option B.
Hence, the correct answer is Option B.
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