Square Root Parent Functions Solutions

Non-Polynomial Parent Functions
Type Absolute Value Square Root Cube Root Reciprocal
Parent equation  y=x  y=x     
Degree does not apply 12    
Domain and Range domain:x|x range:y|y, y0 domain:x|x, x0 range:y|y, y0    
Quadrants Q1 and Q2 Q1    
Because y-coordinates will always be positive because |term|=+term only  are being graphed, so the x- and y-values will be ≥ zero    
Other Characteristics v-shaped, symmetric

Axis of symmetry is x=0, the y-axis
partial inverse of the quadratic function    
Intersects graph vertex at origin, changes directions at origin defined start and end point at the origin    

Example 7

Graph the square root parent function. Name the domain and range in interval and set-builder notation. Then name the end behavior of the graph.

 y=x 

x y
–1 undefined
0 0
1 1
2 1.4142136
3 1.7320508
4 2

Interval notation 

domain: 0, range: 0, 

Set-builder notation

domain:x|x, x0 range:y|y, y0

End behavior

As x+, fx       +      , and as x0,      fx0    

Note

When graphing the square root function, it is helpful to pick values for x that will result in the square root of a perfect square so that the ordered pairs can be graphed accurately.

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