What's the exponent of x? Looks like you inadvertently left that out.
I'm assuming that you mean y = x^2 - x - 2.
This is a quadratic function, and its graph is that of a parabola.
Important points on this parabola are as follows:
x-intercepts, y-intercepts, vertex
Finding these four points will enable you to graph this function nicely.
How do you find the x-intercepts? Set the function = to 0 and solve for x:
x^2 -x -2 = 0 = (x-2)(x+1) = 0, so x = {2,-1}. The y-values are both 0. The intercepts are (2,0) and (-1,0).
How do you find the y-intercept? Let x=0 and find y: y = 0^2 - 0 -2 = -2, so the y-intercept is (0,-2).
Finally, how do you find the vertex? One way would be to find x = -b/(2a),
where a, b and c are the coefficients of a quadratic. Here, a=1, b= -1 and c=-2.
Then x = -(-1) / [2(1)] = 1/2. The x-coordinate of the vertex is 1/2. Subst. this into the original equztion to determine the y-coordinate of the vertex.
Graph all 4 points and then sketch the graph of this parabola.
