eliminate the parameter to find Cartesian equation of the curve.
\[x=t^3+t\] \[y= t^2+2\]
-2 </ t </ 2
t x y -2 -10 6 -1 -2 3 0 0 2 1 2 3 2 10 6
brb gonna refresh open study is lagging me
\(\color{black}{x=t^3+t}\) \(\color{black}{y=t^2+2\quad \Longleftrightarrow \quad y-2=t^2}\) \(\color{black}{x^2=(t^3+t)^2}\) \(\color{black}{x^2=t^6+2t^4+t^2}\) \(\color{black}{x^2=(t^2)^3+2(t^2)^2+(t^2)}\) \(\color{black}{x^2=(y-2)^3+2(y-2)^2+y-2}\)
Side question: Have you learned derivatives?
\(\color{black}{-2\le t \le 2}\) \(\color{black}{\displaystyle \frac{dy}{dx}=\frac{\frac{dy}{dt}}{\frac{dx}{dt}}=\frac{\frac{d}{dt}(t^2+2)}{\frac{d}{dt}(t^3+t)}= \frac{2t}{3t^2+1} }\) This is the slope of the curve. So, the critical numbers are: \(\color{black}{t=-2,0,+2}\) (The 2's are endpoints, 0 is a solution to dy/dx=0) \(\color{black}{t=-2\rightarrow y=(-2)^2+(-2)=2,~x=(-2)^3+(-2)=-10\rightarrow (x,y)=(-10,2)}\) \(\color{black}{t=0~~\rightarrow~~ y=0^2+0=0,~~x=0^3+0=0~~\rightarrow~~ (x,y)=(0,0)}\) \(\color{black}{t=2~~\rightarrow~~ y=2^2+2=6,~~x=2^3+2=10~~\rightarrow~~ (x,y)=(10,6)}\) So, the absolute minimum is (0,0) and the absolute maximum is at (10,6).
So, your domain is \(\color{black}{0\le x\le 10}\)
okay question are we suppose to solve for a certain value?
I just solved for the absolute maximum and absolute minimum of your parametric function, to determine the domain.
how do you know which function to solve ? and how did my teacher get |dw:1479356067640:dw|
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