Graph the function. Compare to the parent graph. State the domain and range.

$\mathit{y}\mathbf{=}\sqrt{\mathbf{x}\mathbf{-}\mathbf{1}\mathbf{.5}}$

Parent graph:The simplest form of the given function is called the parent function of that function and the graph of the parent function is called the parent graph.

Domain: The set of all possible values for which a given function is defined is called domain.

Range: The set of all possible values of the given function is called range.

The given function is: $y=\sqrt{x-1.5}$

To graph a function, find a few coordinates by substituting values of ‘$x$’ and find finding the respective values of ‘$y$’.

$\begin{array}{c}\text{For\hspace{0.17em}\hspace{0.17em}}x=1.5\\ y=\sqrt{1.5-1.5}\\ =\sqrt{0}\\ =0\end{array}$

$\begin{array}{c}\text{For\hspace{0.17em}\hspace{0.17em}}x=2.5,\\ y=\sqrt{2.5-0.5}\\ =\sqrt{1}\\ =1\end{array}$

$\begin{array}{c}\text{For\hspace{0.17em}\hspace{0.17em}}x=5.5,\\ y=\sqrt{5.5-1.5}\\ =\sqrt{4}\\ =2\end{array}$

$\begin{array}{c}\text{For\hspace{0.17em}\hspace{0.17em}}x=10.5,\\ y=\sqrt{10.5-1.5}\\ =\sqrt{9}\\ =3\end{array}$

$\begin{array}{c}\text{For\hspace{0.17em}\hspace{0.17em}}x=17.5,\\ y=\sqrt{17.5-1.5}\\ =\sqrt{16}\\ =4\end{array}$

Plot these coordinates on a coordinate plane and join those points to get the required graph.

The parent function$y=\sqrt{x-1.5}$ is the simplest square root function.

That is, $y=\sqrt{x}$

The graph of the parent function$y=\sqrt{x}$ is given below.

Note: Since the parent function is just used for comparison, it is graphed using the graphing calculator.

The value 1.5 is subtracted inside the square root of the parent function $y=\sqrt{x}$. So the graph$y=\sqrt{x-1.5}$ is the translation of the parent graph $y=\sqrt{x}$.

Since 1.5 is subtracted inside the root, the graph is translated to the right by 1.5 units.

Since the values inside the root must be positive.

$x-1.5\ge 0$

Adding ‘1.5’ on both sides.

$\begin{array}{c}x-1.5+1.5\ge 0+1.5\\ x+0\ge 1.5\\ x\ge 1.5\end{array}$

$x\ge 1.5\Rightarrow x\in [1.5,\infty )$

Therefore, domain: $[1.5,\infty )$

The $y$values are the square root of $x-1.5$. As square roots are positive$y$ takes all the positive real values including zero.

Therefore,$y\ge 0,\Rightarrow y\in [0,\infty )$

Therefore, Range:$[0,\infty )$