Determine all values of $x$ such that the function $y(x)=-x^2+4x-3$ is decreasing.
Antwoord 1 correct
Correct
Antwoord 2 optie
$x>2$
Antwoord 2 correct
Fout
Antwoord 3 optie
$x<-2$
Antwoord 3 correct
Fout
Antwoord 4 optie
$x<2$
Antwoord 4 correct
Fout
Antwoord 1 optie
$x \geq 2$
Antwoord 1 feedback
Correct: $y'(x)=-2x+4$. Hence, $y'(x)=0$ if $x=2$.
Moreover, $y'(x) \leq 0$ if $x\geq 2$. Hence, $y(x)$ is decreasing if $x \geq 2$.
Go on.
Moreover, $y'(x) \leq 0$ if $x\geq 2$. Hence, $y(x)$ is decreasing if $x \geq 2$.
Go on.
Antwoord 2 feedback
Antwoord 3 feedback
Wrong: What is the solution to $-2x+4=0$?
Try again.
Try again.
Antwoord 4 feedback
Wrong: For $x<2$ it holds that $y'(x)>0$.
Try again.
Try again.