$\"\"$

The function is $\"\"$ .

The domain of a function is set of all values of $\"\"$ , which makes the function mathematically correct.

Denominator of the function should not be zero.

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$\"\"$ .

The domain of $\"\"$ is set of all values of $\"\"$ except at $\"\"$ .

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The function is $\"\"$ .

Limit definition of derivatives : $\"\"$ .

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$\"\"$ .

Denominator of the function should not be zero.

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Domain is $\"\"$ .

The derivative of the function $\"\"$ is differentiable for $\"\"$ .

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The derivative of the function $\"\"$ is differentiable for $\"\"$ .