Answer:
[tex]\boxed{(0, 0), (\sqrt{6}, -12-3\sqrt{6}), (-\sqrt{6}, -12+3\sqrt{6})}[/tex]
Step-by-step explanation:
Step 1: Take the derivative of the function with respect to x
[tex]\frac{d}{dx} (\frac{1}{3}x^4-4x^2-3x)\\=\frac{d}{dx} (\frac{1}{3}x^4)-\frac{d}{dx}(4x^2)-\frac{d}{dx}(3x)\\=\frac{4}{3}x^3-8x-3[/tex]
Now, you have the gradient of every point given the x value. We want the gradient to be -3, so,
Step 2: Set the derivative of the function equal to -3 and solve for x
[tex]\frac{4}{3}x^3-8x-3=-3\\\frac{4}{3}x^3-8x=0\\4x(\frac{1}{3}x^2-2)=0\\[/tex]
We can see that one solution is x=0.
The other 2 solutions are:
[tex]\frac{1}{3}x^2-2=0\\\frac{1}{3}x^2=2\\x^2=6\\x=\sqrt{6}, x=-\sqrt{6}[/tex]
Now that we found out the x value, we can plug it in back to the equation to find their respective y value:
x=0: y=0
x=sqrt(6): y=-12-3sqrt(6)
x=-sqrt(6): y=-12+3sqrt(6)
Hence we have our answer.
