Step 1:

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The expression is $\"\"$

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L-Hospital rule

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Suppose $\"\"$ or $\"\"$ , then $\"\"$

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Step 2:

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Evaluate the limit value of the expression.

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$\"\"$

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If $\"\"$ , then $\"\"$ .

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$\"\"$

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Step 3:

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The expression is of the indeterminate form, Apply L-Hospital rule.

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$\"\"$

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$\"\"$

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$\"\"$

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Multiply the numerator and denominator by $\"\"$ .

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$\"\"$

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If $\"\"$ , then $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Solution:

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$\"\"$

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Step 3:

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$\"\"$

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Rewrite the expression.

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$\"\"$

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Simplify the expression.

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Trigonometric sum formula: $\"\"$

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$\"\"$

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Rewrite the expression.

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$\"\"$

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$\"\"$

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If $\"\"$ , then $\"\"$ .

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$\"\"$

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Using Trigonometric Property of limits: $\"\"$ .

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$\"\"$

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Trigonometric half-angle formula: $\"\"$ .

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$\"\"$

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$\"\"$

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