ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)

ĐKXĐ: x>0; x<>9

a) \(P = \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{x \sqrt{x} - 9 \sqrt{x}} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{x + 3 \sqrt{x}} \left.\right)\)

\(= \left(\right. \frac{1}{\sqrt{x} + 3} + \frac{3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right) : \left(\right. \frac{\sqrt{x}}{\sqrt{x} + 3} - \frac{3 \sqrt{x} - 3}{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)} \left.\right)\)

\(= \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}} : \frac{x - 3 \sqrt{x} + 3}{\left(\right. \sqrt{x} + 3 \left.\right) \cdot \sqrt{x}}\)

\(= \frac{x - 3 \sqrt{x} + 3}{\sqrt{x} \left(\right. \sqrt{x} - 3 \left.\right) \left(\right. \sqrt{x} + 3 \left.\right)} \cdot \frac{\sqrt{x} \left(\right. \sqrt{x} + 3 \left.\right)}{x - 3 \sqrt{x} + 3} = \frac{1}{\sqrt{x} - 3}\)