Help!: int(expr,var) function returns the int(expr,var) function

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When i try to make a fucntion described by two indefinite integrals, one of the indefinite integrals returns without being solved.
The variable x an angle between 0 and pi/2.
F_1 is a force.
R_1 and R_2 are lenghts.
%% Variables
syms x;
F_1 = 200; %N
R_1 = 30; % mm
L = 40; % mm
H = 20; % mm
R_2 = 20*(4*cos(x)^2 + sin(x)^2)^(1/2);
%% Equations
m_1(x)= F_1*sin(x)*R_1;
md_1(x)=sin(x)*R_1;
m_2(x)=F_1*R_2*cos(x);
md_2(x)=R_2*cos(x);
ex_1=R_1*m_1(x)*md_1(x);
ex_2=simplify(R_2*m_2(x)*md_2(x))
%% Integration
f(x)=int(ex_1,x) + int(ex_2,x)
f(x) =
2700000*x - 1350000*sin(2*x) - int(1600000*(4 - 3*sin(x)^2)^(3/2)*(sin(x)^2 - 1), x) - It should solve this one, but indstead it just spit out int(expresion,var) just as it was inserted.

Accepted Answer

Cris LaPierre
Cris LaPierre on 17 Apr 2021
That likely means it couldn't solve that one.
Consider using one of the techniques mentioned in these two examples.
  1 Comment
Daniel Møgelbjerg
Daniel Møgelbjerg on 20 Apr 2021
We did it a little different, after realizing that our R_2 in fact was not a variable depending on x, but just another constant value. We are sorry for the eventually wasted time, but thanks a lot for the help.

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R2020a

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