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Find the centre focus,vertex,directrix and axis of each parabola and sketch the graph? (x-1)² = y+2​

User Icekomo
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1 Answer

2 votes

Answer:

Explanation:

The equation for a parabola is of the form y = ax^2 + bx + c, where a, b, and c are constants. The graph of a parabola is a U-shaped curve that is symmetrical about a line called the axis of symmetry.

In the equation (x-1)^2 = y+2, we can rewrite it as y = (x-1)^2 - 2. This is the standard form of a parabola with a = 1, b = 0, and c = -2.

The vertex of the parabola is the point on the graph where the parabola reaches its highest or lowest point. For a parabola in standard form, the vertex is always of the form (h,k), where h and k are the values of x and y, respectively, at the vertex. The vertex of this parabola is (1,-2).

The axis of symmetry of the parabola is a line that divides the parabola into two mirror images. For a parabola in standard form, the axis of symmetry is always the line x = h, where h is the value of x at the vertex. The axis of symmetry of this parabola is the line x = 1.

The directrix of a parabola is a line that is used to define the parabola. For a parabola in standard form, the directrix is always the line y = k + p, where k and p are constants and p is the distance from the vertex to the directrix. The directrix of this parabola is the line y = -2 + p, where p is the distance from the vertex to the directrix.

The focus of a parabola is a point on the axis of symmetry that is used to define the parabola. For a parabola in standard form, the focus is always the point F(h,k+p), where h and k are the values of x and y, respectively, at the vertex, and p is the distance from the vertex to the directrix. The focus of this parabola is F(1,-2+p), where p is the distance from the vertex to the directrix.

To sketch the graph of this parabola, we can start by plotting the vertex at (1,-2). Then we can draw the axis of symmetry, which is the line x = 1. Next, we can choose a value for p and draw the directrix y = -2 + p. Finally, we can use the vertex and focus to plot points on either side of the axis of symmetry, and connect these points to form the U-shaped curve of the parabola.

[asy]

unit size(1cm);

real p = 1.5;

pair F, V;

F = (1,-2+p);

V = (1,-2);

draw((-2,0)--(4,0));

draw((0,-4)--(0,4));

draw((-2,V.y)--(4,V.y),dashed);

draw((F.x,p)--(F.x,-4),dashed);

label("$x$", (4,0), E);

label("$y$", (0,4), N);

label("$y = (x - 1)^2 - 2$", (4,-3), E);

a dot("$F$", F, NW);

a dot("$V$", V, S);

label

User Farna
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7.3k points