Mathematics - Application of Derivative Question with Solution | TestHub

Assume $f(x)f\prime (x)f\prime \prime (x)>0$ for all real $x$. Which sign-pattern graphs are possible? (A) $f>0,f\prime >0,f\prime \prime >0$. (B) $f>0,f\prime <0,f\prime \prime >0$. (C) $f<0,f\prime <0,f\prime \prime <0$. (D) $f<0,f\prime >0,f\prime \prime <0$.