Solve Symbolic Simultaneous equations -- Please help!!
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I am attempting the following code to solve for a,b,c, and d. i keep getting an error saying a does not exist, what i am looking for is a solution for a b c d in terms of n and t
clear all; close all; clc;
syms a b c n t d
eqns = [ a + b + c + d == 0, a*(n^3)+ b*(n^2)+ c*n+ d == t, 3*a*(n^2)+ 2*b*n +c == 0];
S = solve(eqns);
S.a
S.b
S.c
S.d
the error i get is
Reference to non-existent field 'a'.
Error in Untitled (line 7)
S.a
1 个评论
Alan Stevens
2020-10-23
You are asking for four unknowns but you only have three equations!
回答（2 个）
Manvi Goel
2020-10-29
0 个投票
You will require four equations to calculate values of four unknowns. You only have 3 here.
a + b + c + d == 0, (1)
a*(n^3)+ b*(n^2)+ c*n+ d == t, (2)
3*a*(n^2)+ 2*b*n +c == 0, (3)
Walter Roberson
2020-10-29
S = solve(eqns, [a, b, c, d]);
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