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Find the foci , vertices, directrices an...

Find the foci , vertices, directrices and axes of following parabola . Also draw its rough sketch `y = x^(2) - 2x + 3 `

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To solve the problem step by step, we will analyze the given parabola equation \( y = x^2 - 2x + 3 \) and find its foci, vertices, directrices, and axes. ### Step 1: Rewrite the equation in standard form Start with the given equation: \[ y = x^2 - 2x + 3 \] We can complete the square for the quadratic expression in \( x \). ### Step 2: Completing the square 1. Rearrange the equation: \[ y = (x^2 - 2x) + 3 \] 2. Complete the square for \( x^2 - 2x \): \[ x^2 - 2x = (x - 1)^2 - 1 \] 3. Substitute back into the equation: \[ y = (x - 1)^2 - 1 + 3 \] \[ y = (x - 1)^2 + 2 \] ### Step 3: Identify the standard form of the parabola The equation can now be written as: \[ (y - 2) = (x - 1)^2 \] This is in the form \( (y - k) = a(x - h)^2 \), where: - Vertex \( (h, k) = (1, 2) \) - Here, \( a = 1 \). ### Step 4: Determine the parameters For a parabola of the form \( (y - k) = a(x - h)^2 \): - The vertex is at \( (h, k) = (1, 2) \). - The distance \( a \) from the vertex to the focus and directrix is given by \( a = \frac{1}{4p} \), where \( p \) is the distance from the vertex to the focus. Since \( a = 1 \), we have: \[ 4p = 1 \implies p = \frac{1}{4} \] ### Step 5: Find the focus and directrix 1. **Focus**: The focus is located \( p \) units above the vertex (since the parabola opens upwards): \[ \text{Focus} = \left(1, 2 + \frac{1}{4}\right) = \left(1, \frac{9}{4}\right) \] 2. **Directrix**: The directrix is a horizontal line \( p \) units below the vertex: \[ \text{Directrix} = y = 2 - \frac{1}{4} = \frac{7}{4} \] ### Step 6: Identify the axis of symmetry The axis of symmetry is the vertical line through the vertex: \[ \text{Axis} = x = 1 \] ### Summary of Results - **Vertex**: \( (1, 2) \) - **Focus**: \( (1, \frac{9}{4}) \) - **Directrix**: \( y = \frac{7}{4} \) - **Axis of symmetry**: \( x = 1 \) ### Step 7: Rough sketch of the parabola 1. Plot the vertex at \( (1, 2) \). 2. Mark the focus at \( (1, \frac{9}{4}) \). 3. Draw the directrix line at \( y = \frac{7}{4} \). 4. Sketch the parabola opening upwards from the vertex.
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