Solution
= Solution
The <complex sine function> identity $\sin(u+iv)=\sin u\cosh v+i\cos u\sinh v$ follows from the exponential definition of <sine>. With $u=\pi/2$, its imaginary term vanishes, while
$$
\cosh(\ln2)=\frac{e^{\ln2}+e^{-\ln2}}2=\frac{2+1/2}{2}=\frac54.
$$
Consequently \b[the <real part> is $5/4$ and the <imaginary part> is $0$].