1.
Consider f(x)={sin(2πsecx)ex1x;x0,x(2n+1)π2,nZk;x=0f(x) = \begin{cases} \frac{\sin(2\pi \sec x)}{e^x - 1 - x} & ; x \neq 0, \, x \neq (2n+1)\frac{\pi}{2},\, n \in \mathbb{Z} \\ k & ; x = 0 \end{cases}

Value of kk for which f(x)f(x) is continuous at x=0x = 0, is: