Let f (x)= |x^2, sin x; p, -1|, where p is a constant. The value of p for which f^′(0)=1 is:

Let $\displaystyle \mathrm{f}(x)=\left|\begin{array}{cc}x^{2} & \sin x \\ p & -1\end{array}\right|$, where $\displaystyle p$ is a constant. The value of $\displaystyle p$ for which $\displaystyle \mathrm{f}^{\prime}(0)=1$ is :