If alpha=lim _{x rightarrow 0} frac{x cdot 2^ | vedclass

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(C) To find $\alpha$: $\alpha = \lim _{x \rightarrow 0} \frac{x(2^x-1)}{1-\cos x} = \lim _{x \rightarrow 0} \frac{x(2^x-1)}{2 \sin^2(x/2)}$ $= \lim _{

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$\alpha=2 \beta$

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(C) To find $\alpha$: $\alpha = \lim _{x \rightarrow 0} \frac{x(2^x-1)}{1-\cos x} = \lim _{x \rightarrow 0} \frac{x(2^x-1)}{2 \sin^2(x/2)}$ $= \lim _{x \rightarrow 0} \frac{1}{2} \cdot \frac{2^x-1}{x} \cdot \frac{x^2}{\sin^2(x/2)} \cdot \frac{1}{x} = \lim _{x \rightarrow 0} \frac{1}{2} \cdot \frac{2^x-1}{x} \cdot \frac{1}{(\frac{\sin(x/2)}{x/2})^2 \cdot \frac{1}{4}} = \frac{1}{2} \cdot \ln 2 \cdot 4 = 2 \ln 2$ So,$\alpha = 2 \ln 2$ ... $(i)$ To find $\beta$: $\beta = \lim _{x \rightarrow 0} \frac{x(2^x-1)}{\sqrt{1+x^2}-\sqrt{1-x^2}}$ Rationalizing the denominator: $\beta = \lim _{x \rightarrow 0} \frac{x(2^x-1)(\sqrt{1+x^2}+\sqrt{1-x^2})}{(1+x^2)-(1-x^2)} = \lim _{x \rightarrow 0} \frac{x(2^x-1)(\sqrt{1+x^2}+\sqrt{1-x^2})}{2x^2}$ $= \lim _{x \rightarrow 0} \frac{1}{2} \cdot \frac{2^x-1}{x} \cdot (\sqrt{1+x^2}+\sqrt{1-x^2}) = \frac{1}{2} \cdot \ln 2 \cdot (1+1) = \ln 2$ So,$\beta = \ln 2$ ... $(ii)$ From $(i)$ and $(ii)$,we get $\alpha = 2\beta$.

If $\alpha=\lim _{x \rightarrow 0} \frac{x \cdot 2^x-x}{1-\cos x}$ and $\beta=\lim _{x \rightarrow 0} \frac{x \cdot 2^x-x}{\sqrt{1+x^2}-\sqrt{1-x^2}}$,then

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