The problem provides the quadratic function $y = x^2 - 2x - 3$ and an incomplete table of values for $x$ and $y$. (i) Find the value of $y$ when $x = 1$. (ii) Draw the graph of the function using a suitable scale on graph paper. (iii) Write the equation of the axis of symmetry using the graph. (iv) Describe the behavior of $y$ in the interval $1 < x < 3$. (v) Express the given function in the form $y = (a - x)^2 - b$, where $a$ and $b$ are constants.
2025/6/1
1. Problem Description
The problem provides the quadratic function and an incomplete table of values for and .
(i) Find the value of when .
(ii) Draw the graph of the function using a suitable scale on graph paper.
(iii) Write the equation of the axis of symmetry using the graph.
(iv) Describe the behavior of in the interval .
(v) Express the given function in the form , where and are constants.
2. Solution Steps
(i) To find the value of when , substitute into the equation :
(ii) To draw the graph, plot the points given in the table, including the point (1, -4) we just found:
(-2, 5), (-1, 0), (0, -3), (1, -4), (2, -3), (3, 0), (4, 5)
(iii) The axis of symmetry is the vertical line that passes through the vertex of the parabola. The vertex is at , so the equation of the axis of symmetry is .
(iv) In the interval , the value of increases. The function decreases from to , reaching its minimum , then increases from to , where .
(v) To express the given function in the form , we need to complete the square for the given quadratic:
.
Therefore, , which is in the form , with and .
3. Final Answer
(i) when .
(iii) Equation of the axis of symmetry:
(iv) In the interval , y increases.
(v)