Dear slapmaxwell1,
By definition,
By simplification,
Therefore, sinh(x+y) = sinh(x)cosh(y) + cosh(x)sinh(y)
Hope this helps.
sinh(x+y) = sinh(x)cosh(y) + cosh(x)sinh(y)
im not sure how to verify this, i suppose i would try to plug numbers into the equation and solve both sides. i suppose im looking for a more efficient way to verify this without having to plug and chug. thanks in advance