Weird results using solve function to solve the system of 2 equations

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Hi, I'm getting weird results solving the system of two equations, can anyone pease help me or suggest the other solver?
Here is the code:
clc
close all
clear all
T_i = 0;
T_1 = 0;
T_2 = 0;
n_i = 0;
n_1 = 0;
n_2 = 0;
eNBi_coordinates = zeros(1, 2);
eNB1_coordinates = zeros(1, 2);
eNB2_coordinates = zeros(1, 2);
eNBi_coordinates = [0 100];
eNB1_coordinates = [0, 0];
eNB2_coordinates = [100, 0];
x_i = eNBi_coordinates(1);
y_i = eNBi_coordinates(2);
x_1 = eNB1_coordinates(1);
y_1 = eNB1_coordinates(2);
x_2 = eNB2_coordinates(1);
y_2 = eNB2_coordinates(2);
C = 3e8;
RSTD_1 = 167e-9;
RSTD_2 = 334e-9;
syms x_t y_t
[solx_t, soly_t] = solve(sqrt((x_t - x_i)^2+(y_t - y_i)^2)/C - sqrt((x_t - x_1)^2 + (y_t - y_1)^2)/C ...
+ (T_i - T_1) + (n_i - n_1) - RSTD_1 == 0,...
sqrt((x_t - x_i)^2+(y_t - y_i)^2)/C...
- sqrt((x_t - x_2)^2+(y_t - y_2)^2)/C + (T_i-T_2) + (n_i - n_2) - RSTD_2 == 0)
and the results i'm getting for [x_t, y_t] are:
solx_t =
(3966588620774505912890625*80204523989384538823263623044267146941326844497824520329275840654591478382575236575064977389815784125651517951641807^(1/2))/944770725576785769100984182366758081137891047164257164584802962242160716020711424 + 1631175376265062325404557393255693262302775/43556142965880123323311949751266331066368
soly_t =
1631175376265062325404557393255693262302775/43556142965880123323311949751266331066368 - (3966588620774505912890625*80204523989384538823263623044267146941326844497824520329275840654591478382575236575064977389815784125651517951641807^(1/2))/944770725576785769100984182366758081137891047164257164584802962242160716020711424
awaiting for your help.
Regards, Botir

Accepted Answer

Star Strider
Star Strider on 10 Jan 2015
That is normal for the Symbolic Math Toolbox. If you want a simplified result, use the vpa function:
vpa_x = vpa(solx_t,6)
vpa_y = vpa(soly_t,6)
producing:
vpa_x =
75.0502
vpa_y =
-0.150251
See the documentation on vpa for details.

More Answers (1)

Batir Ismailov
Batir Ismailov on 10 Jan 2015
Thanks a lot, it really helps me.

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