 Trig vs hyperbolic handling differences in Prime CAS - Printable Version +- HP Forums (https://archived.hpcalc.org/museumforum) +-- Forum: HP Museum Forums (https://archived.hpcalc.org/museumforum/forum-1.html) +--- Forum: Old HP Forum Archives (https://archived.hpcalc.org/museumforum/forum-2.html) +--- Thread: Trig vs hyperbolic handling differences in Prime CAS (/thread-255214.html) Trig vs hyperbolic handling differences in Prime CAS - Michael de Estrada - 11-08-2013 I posted this previously, but received no response so I'm trying again . When I enter COS(x)^2+SIN(x)^2 in CAS I get the result 1, which is correct since this result is true regardless of the value of x. However, if I enter COSH(x)^2-SINH(x)^2 in CAS I should also get 1 as a result, however, I simply get COSH(x)^2-SINH(x)^2 as a result instead. If I replace x with a numerical value instead, then I get the proper result of 1. Why ? And yes I am in radians mode and have Exact unchecked when I do this. Re: Trig vs hyperbolic handling differences in Prime CAS - Mark Hardman - 11-08-2013 Try using hyp2exp: simplify(hyp2exp(cosh(x)^2-sinh(x)^2)) Gives you the answer you are looking for. Re: Trig vs hyperbolic handling differences in Prime CAS - Michael de Estrada - 11-08-2013 Thank you very much. Giving it some thought, this makes a lot of sense because while trig functions like cosine and sine are primary, hyperbolics like cosh and sinh are derived from the exponential function, which is primary. Re: Trig vs hyperbolic handling differences in Prime CAS - Mark Hardman - 11-08-2013 Agreed. There is value in seeing the intermediate result of: ((exp(x)+1/exp(x))/2)^2-((exp(x)-1/exp(x))/2)^2