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Evaluate lim(xto0)(cosecx)^(x)....

Evaluate `lim_(xto0)(cosecx)^(x)`.

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To evaluate the limit \( \lim_{x \to 0} (\csc x)^x \), we will follow these steps: ### Step 1: Set up the limit Let \( y = (\csc x)^x \). We want to find \( \lim_{x \to 0} y \). ### Step 2: Take the natural logarithm Taking the natural logarithm on both sides, we have: \[ \ln y = x \ln (\csc x) \] ### Step 3: Evaluate the limit of the logarithm Now we need to evaluate: \[ \lim_{x \to 0} \ln y = \lim_{x \to 0} x \ln (\csc x) \] As \( x \to 0 \), \( \csc x = \frac{1}{\sin x} \) approaches infinity, and thus \( \ln (\csc x) \) approaches infinity. Therefore, we have the indeterminate form \( 0 \cdot \infty \). ### Step 4: Rewrite the limit To resolve the indeterminate form, we rewrite the limit: \[ \lim_{x \to 0} x \ln (\csc x) = \lim_{x \to 0} \frac{\ln (\csc x)}{\frac{1}{x}} \] This transforms our limit into the form \( \frac{\infty}{\infty} \). ### Step 5: Apply L'Hôpital's Rule Now we can apply L'Hôpital's Rule: \[ \lim_{x \to 0} \frac{\ln (\csc x)}{\frac{1}{x}} = \lim_{x \to 0} \frac{\frac{d}{dx} \ln (\csc x)}{\frac{d}{dx} \left(\frac{1}{x}\right)} \] Calculating the derivatives: - The derivative of \( \ln (\csc x) \) is \( -\cot x \). - The derivative of \( \frac{1}{x} \) is \( -\frac{1}{x^2} \). Thus, we have: \[ \lim_{x \to 0} \frac{-\cot x}{-\frac{1}{x^2}} = \lim_{x \to 0} \frac{x^2 \cot x}{1} = \lim_{x \to 0} x^2 \frac{\cos x}{\sin x} \] ### Step 6: Simplify the limit As \( x \to 0 \), \( \frac{\sin x}{x} \to 1 \), so: \[ \lim_{x \to 0} x^2 \frac{\cos x}{\sin x} = \lim_{x \to 0} x^2 \cdot \frac{1}{1} = 0 \] ### Step 7: Conclude the limit for \( y \) Since \( \lim_{x \to 0} \ln y = 0 \), we can exponentiate to find \( y \): \[ y = e^{\lim_{x \to 0} \ln y} = e^0 = 1 \] ### Final Answer Thus, the limit is: \[ \lim_{x \to 0} (\csc x)^x = 1 \] ---
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