How do I solve this equation in MatLab?

Find the area of the region bounded by the hyperbola 9x^2−4y^2=36 and the line x=3.
I cannot find out the proper way to input this into MatLab. It requires trig substitution so I believe the problem stems from there but I am new to MatLab and don't know what I can do to fix it.
Here is my code:
>> syms x
>> EQ = 3*sqrt(x^2-4)
EQ =
3*(x^2 - 4)^(1/2)
>> A = int(EQ,2,3)
A =
log(161 - 72*5^(1/2)) + (9*5^(1/2))/2
>>
Here is the actual answer to the problem:
(9/2)*sqrt(5) - 6*ln((3 + sqrt(5))/2)

 Respuesta aceptada

KSSV
KSSV el 24 de Jun. de 2021
Why worry the final answer is same right?
syms x
eq = 3*sqrt(x^2-4) ;
A1 = int(eq,2,3) ;
A2 = (9/2)*sqrt(5) - 6*log((3 + sqrt(5))/2) ;
[double(A1) A2]
ans = 1×2
4.2878 4.2878

4 comentarios

Isaac Hewitt
Isaac Hewitt el 24 de Jun. de 2021
Editada: Isaac Hewitt el 24 de Jun. de 2021
Can you explain this more, how is this the same answer?
Yeah I just did this and I have no idea how you did this at all. Please explain what is happening.
KSSV
KSSV el 24 de Jun. de 2021
Answer is converted into double from symbolic class.
Isaac Hewitt
Isaac Hewitt el 24 de Jun. de 2021
Editada: Isaac Hewitt el 24 de Jun. de 2021
What does that mean? I just downloaded MatLab for a class a few days ago, I have no idea what that means.
I ask this because in all my calculations
log(161 - 72*5^(1/2)) + (9*5^(1/2))/2 = 7.55445
(9/2)*sqrt(5) - 6*ln((3 + sqrt(5))/2) = 4.28776
format long g
syms x
eq = 3*sqrt(x^2-4)
eq = 
A1 = int(eq,2,3)
A1 = 
A2 = (9/2)*sqrt(5) - 6*log((3 + sqrt(5))/2)
A2 =
4.28776399803381
simplify(A1 - A2)
ans = 
double(A1 - A2)
ans =
2.3429264568019e-16
log(161 - 72*5^(1/2)) + (9*5^(1/2))/2
ans =
4.28776399803129
.... not 7.55445

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R2021a

Preguntada:

el 24 de Jun. de 2021

Comentada:

el 24 de Jun. de 2021

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