Questions: Question 6
Choose the equation representing the graph below.
f(x)=1+√x
f(x)=√(1-x)
f(x)=√(x-1)
None of these choices
f(x)=-√x+1
Transcript text: Question 6
Choose the equation representing the graph below.
$f(x)=1+\sqrt{x}$
$f(x)=\sqrt{1-x}$
$f(x)=\sqrt{x-1}$
None of these choices
$f(x)=-\sqrt{x}+1$
Solution
Solution Steps
Step 1: Analyze the graph
The graph starts at the point (1, 0) and passes through the point (0, 1). It is a decreasing function and looks like a square root graph reflected over the y-axis and shifted one unit to the right.
Step 2: Test the first equation
$f(x) = 1 + \sqrt{x}$. If $x=0$, $f(0) = 1 + \sqrt{0} = 1$. If $x=1$, $f(1) = 1 + \sqrt{1} = 2$. So this equation doesn't work.
Step 3: Test the second equation
$f(x) = \sqrt{1-x}$. If $x=0$, $f(0) = \sqrt{1-0} = 1$. If $x=1$, $f(1) = \sqrt{1-1} = 0$. This looks promising so far. If $x=-3$, $f(-3) = \sqrt{1-(-3)} = \sqrt{4} = 2$, which also appears to lie on the graph.
Step 4: Test the third equation
$f(x) = \sqrt{x-1}$. If $x=0$, $f(0) = \sqrt{0-1} = \sqrt{-1}$, which is not a real number, so this equation doesn't work.
Step 5: Test the fourth equation
$f(x) = -\sqrt{x} + 1$. If $x=0$, $f(0) = -\sqrt{0} + 1 = 1$. If $x=1$, $f(1) = -\sqrt{1} + 1 = 0$. If $x=4$, $f(4) = -\sqrt{4} + 1 = -1$. The point (4, -1) is not on the graph.