Hi

I need help on the following questions:

1) Express sinh(x+y) in terms of sinh(x), sinh(y), cosh(x), cosh(y)

2) Given cosh $\displaystyle u=\frac{5}{4}$ find values of sinh(u)

This is what i have done:

made $\displaystyle u=\frac{5}{4}$

so sinh(u) = 1.89.

What is wrong??

P.S