Animated Solution for Mathematics - Functions: Draw the graph of y=∣x∣1/2 for −1≤x≤1.
Visualized Solution
Introduction to y=∣x∣21
Function: y=∣x∣21
Given Domain: x∈[−1,1]
We need to plot this on the Cartesian plane.
The Origin Point
Let's check the value at x=0.
y=∣0∣21=0
The graph passes through the origin (0,0).
Breaking Down the Modulus
The function contains a modulus: ∣x∣
Definition of modulus:
∣x∣=x if x≥0
∣x∣=−x if x<0
Case 1: Positive x
Case 1: x≥0 (Right side of y-axis)
In this region, ∣x∣=x
Substitute into the function: y=(x)21
Graphing Case 1
y=x21⟹y=x
This is the upper half of a rightward opening parabola.
At x=1, y=1=1.
Case 2: Negative x
Case 2: x<0 (Left side of y-axis)
In this region, ∣x∣=−x
Substitute into the function: y=(−x)21
Graphing Case 2
y=(−x)21⟹y=−x
Since x is negative, −x is positive, making the square root real.
At x=−1, y=−(−1)=1=1.
Symmetry Analysis
Let's verify the symmetry mathematically.
Replace x with −x:
f(−x)=∣−x∣21
Since ∣−x∣=∣x∣, we get:
f(−x)=∣x∣21=f(x)
Conclusion: Even Function
Because f(−x)=f(x), the function is an Even Function.
Even functions are always symmetric about the y-axis.
The graph consists of two symmetric parabolic arcs meeting at the origin.
00:00 / 00:00
The Sigma Insight: Classification of Functions
Solution Diagram
Analyzing the Setup
Imagine you are standing on the Cartesian plane, ready to map out a function that seems simple but hides a beautiful geometric secret. We are tasked with graphing y=∣x∣21 within the domain x∈[−1,1].
This is not just a line; it is a journey into the heart of symmetry and piecewise behavior.
The Anchor Point
The Origin
Every great journey starts with a single step, and for this function, that step is the origin. When we test x=0, the math becomes incredibly elegant:
y=∣0∣21=0
This confirms that our graph is anchored firmly at the point (0,0). This point acts as the pivot for our entire construction.
The Modulus Split
Breaking the Barrier
The modulus function ∣x∣ is the gatekeeper of this problem. It forces us to split our world into two distinct realities.
By definition, ∣x∣=x when x≥0, and ∣x∣=−x when x<0. We cannot treat this as one monolithic equation; we must respect the boundary at the y-axis.
The Right Wing
The Parabolic Ascent
For the region where x≥0, our function simplifies beautifully to y=x21, or y=x. If you have spent time with conic sections, you will recognize this instantly.
It is the upper half of a parabola that opens to the right. As x moves from 0 to 1, y climbs from 0 to 1. It is a smooth, accelerating curve that defines the right side of our graph.
The Left Wing
The Mirror Image
Now, we cross the y-axis into the territory where x<0. Here, the modulus demands that ∣x∣=−x. Our function becomes y=(−x)21, or y=−x.
Do not be alarmed by the negative sign! Since x is negative, −x is positive, keeping our output firmly in the realm of real numbers. At x=−1, we find:
y=−(−1)=1=1
This creates a mirror image of our right-wing parabola, opening to the left.
The Symmetry of the Even Function
When we step back and look at the two arcs meeting at the origin, we see a perfect balance. Mathematically, we have proven this is an Even Function because f(−x)=f(x).
This symmetry is not just a visual treat; it is a fundamental property that makes the graph a mirror image across the y-axis. You have successfully navigated the piecewise definition, visualized the parabolic arcs, and understood the symmetry.
You have not just drawn a graph; you have understood the soul of the function.