$\"\"$

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The function is $\"\"$ .

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Apply derivative on each side with respect to $\"\"$ .

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$\"\"$

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Apply quotient rule of differentiation: $\"\"$ .

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In this case $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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The slope of the tangent is $\"\"$ .

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$\"\"$

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To find horizontal tangent by equating slope of the tangent is zero.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Horizontal tangent at $\"\"$ .

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$\"\"$

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Find the points at which the function has a horizontal tangents.

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Horizontal tangent at $\"\"$ .

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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The point is $\"\"$ .

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Horizontal tangent at the point $\"\"$ .

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$\"\"$

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Horizontal tangent at the point $\"\"$ .