To be turned in on Monday:
 For what values of $k$ is $$ f(x) = \cases{x^2+2kx+k^2& \text{for $x<1$}\\[3px] 4kx& \text{for $x\ge 1$}\cr} $$ continuous at $x=1$?
Fully justify your answer (for instance, you might want to show that, for your value(s) of $k$, $f$ statisfies the definition of continuity at $x=1$. Make sure you give reasons for all of your claims.)
 Compute the derivatives of the following function: $f(x) = (x^23x)e^{x^2}$

