CAS Simplify: HP Prime vs. TI Nspire

[Joe Horn]

(08-13-2018 08:24 PM)JDW Wrote:  If you can get your Prime to simplify the said expression down to (sin(x))^2 in a single step, please provide the procedure.

Prime, and the 50g before it, offer many specialized flavors of simplification. The most appropriate Prime function for your purposes is probably the trigsin() function:

trigsin(sin(x)*cos(x)*tan(x)) --> sin(x)^2

Many math expressions do NOT have a single correct "fully simplified" form, but rather have many simplified forms of varying usefulness in varying situations. Prime and the 50g are designed to teach students to distinguish between these different types of simplification, and to use whichever one is appropriate to their current situation.

The most common mistake students make is thinking that "simplified form" means "shortest form". But that's often not true. Easy example: both of the following expressions are equivalent. Which is the simplified form?

A: (x+1)^5
B: x^5+5*x^4+10*x^3+10*x^2+5*x+1

Answer: B, even though it's much longer.