Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
0 votes

The curve $y=e^{-x} $ is

\[\begin{array}{1 1}(1)concave\;upward\;for \;x>0&(2)concave\;downward\;for\;x>0\\(3)every \;where\;concave\;upward &(4)every\;where\;concave\;downward\end{array}\]

Can you answer this question?

1 Answer

0 votes
$\large\frac{dy}{dx}$$=-e^{-x} x-1=e^{-x}$
$\large\frac{d^2y}{dx^2}$$=-e^{-x} <0$ for all x
The given curve is concave downward every where
Hence 4 is the correct answer.
answered May 20, 2014 by meena.p
Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App