Why does the SIMPLE command in Symbolic Math Toolbox not produce a simplification in a hyperbolic term?

The following code:

syms b;

P1=sinh(b);

P2=(exp(b)-exp(-b))/2;

simple(P1-P2);

does not return 0 which it should evaluate to.

Answer 1

[MathWorks Support Team]

This issue arises due to the fact that the hyperbolic term should be converted to the exponential form prior to calling the function SIMPLE. The workaround is to issue the following call to MAPLE via MATLAB:

syms b;

P1=sinh(b);

P2=(exp(b)-exp(-b))/2;

simplify(maple('convert',P1,'exp') - P2);

The following is another method to get the right output:

taylor(P1-P2,1);