1. Planteamos el problema: Dadas las funciones $f(x) = \frac{2}{x}$ y $g(x) = \frac{-3x}{x+1}$, realizaremos las operaciones indicadas.
2. Recordemos las operaciones con funciones:
- Suma: $(f+g)(x) = f(x) + g(x)$
- Resta: $(f-g)(x) = f(x) - g(x)$
- Producto: $(f \cdot g)(x) = f(x) \times g(x)$
- Cociente: $(\frac{f}{g})(x) = \frac{f(x)}{g(x)}$
- Composición: $(f \circ g)(x) = f(g(x))$
3. Calculamos cada operación:
**a) Suma $(f+g)(x)$:**
$$(f+g)(x) = \frac{2}{x} + \frac{-3x}{x+1} = \frac{2(x+1)}{x(x+1)} + \frac{-3x \cdot x}{x(x+1)} = \frac{2x + 2 - 3x^2}{x(x+1)}$$
**b) Resta $(f-g)(x)$:**
$$(f-g)(x) = \frac{2}{x} - \frac{-3x}{x+1} = \frac{2(x+1)}{x(x+1)} - \frac{-3x \cdot x}{x(x+1)} = \frac{2x + 2 + 3x^2}{x(x+1)}$$
**c) Producto $(f \cdot g)(x)$:**
$$(f \cdot g)(x) = \frac{2}{x} \times \frac{-3x}{x+1} = \frac{2 \cancel{x}}{\cancel{x}} \times \frac{-3}{x+1} = \frac{-6}{x+1}$$
**d) Cociente $(\frac{f}{g})(x)$:**
$$(\frac{f}{g})(x) = \frac{\frac{2}{x}}{\frac{-3x}{x+1}} = \frac{2}{x} \times \frac{x+1}{-3x} = \frac{2(x+1)}{x \cdot -3x} = \frac{2(x+1)}{-3x^2}$$
4. Ahora calculamos las composiciones:
**a) $(f \circ g)(x) = f(g(x))$:**
$$f(g(x)) = f\left(\frac{-3x}{x+1}\right) = \frac{2}{\frac{-3x}{x+1}} = 2 \times \frac{x+1}{-3x} = \frac{2(x+1)}{-3x}$$
**b) $(g \circ f)(x) = g(f(x))$:**
$$g(f(x)) = g\left(\frac{2}{x}\right) = \frac{-3 \cdot \frac{2}{x}}{\frac{2}{x} + 1} = \frac{-\frac{6}{x}}{\frac{2}{x} + 1} = \frac{-6}{x} \times \frac{1}{\frac{2}{x} + 1} = \frac{-6}{x} \times \frac{1}{\frac{2+x}{x}} = \frac{-6}{x} \times \frac{x}{2+x} = \frac{-6}{2+x}$$
Respuesta final:
- $(f+g)(x) = \frac{2x + 2 - 3x^2}{x(x+1)}$
- $(f-g)(x) = \frac{2x + 2 + 3x^2}{x(x+1)}$
- $(f \cdot g)(x) = \frac{-6}{x+1}$
- $(\frac{f}{g})(x) = \frac{2(x+1)}{-3x^2}$
- $(f \circ g)(x) = \frac{2(x+1)}{-3x}$
- $(g \circ f)(x) = \frac{-6}{2+x}$
Funciones Operaciones A69Bc1
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