Consider the function $y(x)=\sqrt{x+3}$. Which of the following statements is true?
The function is concave.
The function is convex.
The function is neither convex nor concave.
That cannot be determined on the basis of the given information.
Consider the function $y(x)=\sqrt{x+3}$. Which of the following statements is true?
Antwoord 1 correct
Correct
Antwoord 2 optie
The function is convex.
Antwoord 2 correct
Fout
Antwoord 3 optie
The function is neither convex nor concave.
Antwoord 3 correct
Fout
Antwoord 4 optie
That cannot be determined on the basis of the given information.
Antwoord 4 correct
Fout
Antwoord 1 optie
The function is concave.
Antwoord 1 feedback
Correct: From $y''(x)=-\frac{1}{4}(x+3)^{-\frac{3}{2}}$ it follows that $y''(x)<0$ for every $x>-3$. Hence, the function is concave.

Go on.
Antwoord 2 feedback
Wrong: If $y''(x)<0$ for every $x>-3$, then the function is concave.

See the Second-order condition.
Antwoord 3 feedback
Wrong: Determine the second-order derivative $y''(x)$.

See the Second-order condition.
Antwoord 4 feedback
Wrong: Determine the second-order derivative $y''(x)$.

See the Second-order condition.