Substitution after differentiation (easy)?

3 Ansichten (letzte 30 Tage)
Mark
Mark am 4 Jun. 2012
I am trying to substitute the variable x after differentiating y with respect to x. Any ideas on the final step?
>> syms x;
>> y=5*x^2+6*x-3;
>> y1=diff(y,x);
after this I cannot use
>> x=3;
>> y1
because this just gives me y1 in terms of x

Akzeptierte Antwort

Walter Roberson
Walter Roberson am 4 Jun. 2012
subs(y1)
Caution: the result in this case would be a symbolic number; use double() on the result if you need a floating point number that MATLAB itself can compute with.

Weitere Antworten (0)

Kategorien

Mehr zu Symbolic Math Toolbox finden Sie in Help Center und File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by