# How to substitute to a variable in a function with a constant

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ijsonvjksrefdsb on 6 Sep 2022
Edited: Stephen23 on 18 Oct 2022
I'm trying to substitute some values of t to this equation:
x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3;
Unrecognized function or variable 't'.
But it won't work because of the c. The assignment is to avoid using symbolic math, how can I bypass this error? Like it would simply substitute the values of t with c remaining undefined. Thanks
Stephen23 on 18 Oct 2022
Edited: Stephen23 on 18 Oct 2022
How to substitute to a variable in a function with a constant
I'm trying to substitute some values of t to this equation:
x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3;
Unrecognized function or variable 't'.
But it won't work because of the c. The assignment is to avoid using symbolic math, how can I bypass this error? Like it would simply substitute the values of t with c remaining undefined. Thanks

Chunru on 6 Sep 2022
Edited: Chunru on 6 Sep 2022
% Specify the values beforehand
t = 0:.1:5;
c = 2;
x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3;
plot(t, x)
% symbolic computation
syms t c x
x = 3.0 + 4.0.*t + c.*t.^2 - 2.0.*t.^3
x =
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Chunru on 6 Sep 2022
Do you want to have symbolic computation?