- #1
PFuser1232
- 479
- 20
Osborn's rule:
"The prescription that a trigonometric identity can be converted to an analogous identity for hyperbolic functions by expanding, exchanging trigonometric functions with their hyperbolic counterparts, and then flipping the sign of each term involving the product of two hyperbolic sines."
I understand how to apply Osborn's rule to identities involving a product of two hyperbolic sines, but I'm not entirely sure what happens when there is an "odd/even product" of hyperbolic sines. For instance, does ##\sin^4{x}## become ##-\sinh^4{x}##? What about ##\sin^3{x}##?
"The prescription that a trigonometric identity can be converted to an analogous identity for hyperbolic functions by expanding, exchanging trigonometric functions with their hyperbolic counterparts, and then flipping the sign of each term involving the product of two hyperbolic sines."
I understand how to apply Osborn's rule to identities involving a product of two hyperbolic sines, but I'm not entirely sure what happens when there is an "odd/even product" of hyperbolic sines. For instance, does ##\sin^4{x}## become ##-\sinh^4{x}##? What about ##\sin^3{x}##?