Answer:
y = (-x)^3 - 4
Step-by-step explanation:
Ok, for the function:
y = x^3
When x = 0, we have:
y = 0^3 = 0
So the original graph passes through the point (0, 0)
If we look at the given graph, we can see that the y-intercept (the value of y when x = 0) is:
y = -4
So, this is the graph of y = x^3 moved down 4 units.
You can also see that the graph goes downward as x increases (and up as x decreases) while for the function:
y = x^3
as x increases, we should see that y also increases.
Then we have a reflection across the x-axis.
Ok, now let's describe a vertical shift.
For a general function f(x), a vertical shift of N units is written as:
g(x) = f(x) + N
if N is positive, the shift is upwards
if N is negative, the shift is downwards.
And for a function f(x), a reflection across the x-axis is written as:
g(x) = - f(x)
Here we first apply the reflection across the x-axis, so we get:
g(x) = -f(x)
now we apply the shift 4 units downwards
g(x) = - f(x) - 4
replacing f(x) by our function, x^3
we get:
g(x) = -x^3 - 4
And because of the odd power, we can write:
-x^3 = (-x)^3
Then the function is:
g(x) = (-x)^3 - 4
The correct option is the last one.
y = (-x)^3 - 4
