Hello Sir, how can I know to get the real root

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shunmugam hemalatha 2021-6-2

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/845860-hello-sir-how-can-i-know-to-get-the-real-root

clc

clear all

C=10;

A=50;

R=2;

alp=200;

C2=1;

theta=0.5;

beta=5;

i=0.03;

del=0.05;

syms T tow

x = '((260*0.7)/2)+((260*5*T)/3)+((260*0.7*T*((exp(-0.05*tow))+0.1))/3)+((260*5*(T^2)*((exp(-0.05*tow))+0.1))/8)-(40/(T^2))+(50*((3*260*0.09*(exp(-0.05*tow)))-(2*T*260*0.1*0.09*(exp(-0.05*tow)))-(2*T*260*(0.1^2)))/6)';

y ='1-((0.05*260*0.7*(T^2)*0.09*(exp(-0.05*tow)))/6)-((0.05*260*5*(T^3)*0.09*(exp(-0.05*tow)))/24)-(50*0.05*T*0.09*(exp(-0.05*tow))*((3*260-260*0.1*T)/6))';

[T, tow]= solve(x, y)

TC =(c0/T)+(1/T)*(((a*h*(T^2))/2)+((a*r*(T^3))/6)

+((((a*y0*(exp(u*tow))+b)/2)*((h*(T^3)/3)+((r*(T^4)/12))))))+(cd/T)*((((T^2)*y0*(exp(-u*tow)))*(3*a-a*b*T))/6)

+((tow*T)/T);

Answer: TC =230.390; T = 0.388; tow = 48.420;

But I’m getting the answer as an imaginary root.

T =1.7453101688240471531481815578689 + 10.878829179983172648511290985693i

tow =26.742995017209863035778397901947 - 42.57449622896936878786437604528i

Can anyone help me to find the real root and for TC.