Exercise 6.12 A Sallen-Key low-pass filter circuit

Given is the following second-order Sallen-Key low-pass filter:

a)

Show that the transfer function of this filter is $H(\mathit{j\omega })=\frac{1}{1+2\mathit{j\omega RC}+j^2{\omega }^2{R}^2{C}^2}$ for $A\to \infty$.

b)

Draw the Bode plot (magnitude and phase) of this $H(\mathit{j\omega })$