How is the graph of the square root function similar to a parabola? How is it different?

Why might they be related?

it is a parabola, with its axis along the x-axis, rather than the y-axis.

Note that

y = √x is only the top half.
y^2 = x shows both halves.

The graph of the square root function and a parabola, such as y = x^2, share some similarities, but they also have important differences.

Similarities:
1. Both the square root function and a parabola are symmetric about a certain point on the graph. The square root function is symmetric about the y-axis, while a parabola is symmetric about its vertex.
2. Both graphs are continuous, meaning they have no breaks or holes in their shape.
3. Both the square root function and a parabola can extend indefinitely in certain directions, either towards negative or positive infinity.

Differences:
1. The shape of the graphs is different. The square root function starts from the origin (0, 0) and gradually increases, whereas a parabola opens upwards or downwards and has a more pronounced curved shape.
2. The square root function only takes non-negative values, while a parabola can have negative y-values.
3. The x-values where the graphs intersect the x-axis are different. The square root function intersects the x-axis at 0 and then continues to increase. A parabola intersects the x-axis at one or two points, depending on its orientation.

Why might they be related?
Both the square root function and a parabola belong to the family of functions known as "quadratic functions" and share some fundamental characteristics. A quadratic function is one that has a variable raised to the power of two (x^2), and both the square root function and a parabola fit this pattern.

Additionally, the square root function can be considered as a special case of a parabola. If we consider the parabola y = x^2 and restrict the domain to only non-negative x-values, we obtain the square root function y = √x. In this sense, the square root function is related to a parabola but represents only half of its graph.

In conclusion, while the square root function and a parabola share some similarities as well as being members of the quadratic function family, they also have notable differences in their shapes and range of values.