# how can i solve this error

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sajjad barzigar on 2 Aug 2020 at 18:36
i writed this code and i want to integral the sum of Egb and Egs but i get this error
Error using integral (line 82)
First input argument must be a function handle.
and this error
Error in figure (line 28)
Eg=integral(Egs+Egb,0,TETAmax,TETA);
this is the code
clc
clear all
syms TETA
S0=613e9;
Sp=3.7e9;
Rin=27.5e-3;
Rout=31.5e-3;
h=15e-3;
for t=0.001:0.0001:0.0014;
TETAmax=-3.661*((h/t)^-1.14)+2.589;
DELTAmax=h-t-(h/(2*TETAmax));
R=Rin+(t/2);
Egb=pi*S0*(t^2)*((TETA*4*R)+h-(h*cos(TETA)))/((3^(0.5))*(TETA))
Egs=pi*S0*(h^2)*t*(TETA*sin(TETA)+cos(TETA)-1)/(2*(TETA)^2)
Eg=integral(Egs+Egb,0,TETAmax,TETA);
end
what is wrong?thank you for your help.

Walter Roberson on 2 Aug 2020 at 18:45
integral() is reserved for numeric integration. You are doing integration of symbolic expression. You need to use int() or vpaintegral() for that.

Walter Roberson about 23 hours ago
What is the valid range of values for h/t ? Sometimes equations are approximately valid within a particular range of interest while being too wrong outside of the area of interest.
normaly between 12 to 20 i think.but they didnt mention any kind of valid range for the answer.
any way thank you for every thing :)