Find the relation between 2 variables

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Debdut
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Homework Statement
Find the relation between Vin and Vout
Relevant Equations
V1 = (-gm1 * Vin + s* C1 * Vout) / (gmc + s * C1)
gmc * V1 + s * C2 * Vout = Vx * (s * rb * C2 + 1) / rb
s * C1 * (V1 - Vout) + s * C2 * (Vx - Vout) = gm2 * Vx + Vout / ro2
Here is the equation I obtain after simplification, I don't know if it is correct:
gmc * V1 + s * C2 * Vout = [{s * (C1 + C2) * ro2 + 1} * Vout - s * C1 * ro2 * V1] * (s * rb * C2 + 1) / {ro2 * rb * (s * C2 - gm2)}

I need to eliminate V1 to find the relation between Vin and Vout.
 
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Debdut said:
V1 = (-gm1 * Vin + s* C1 * Vout) / (gmc + s * C1)
gmc * V1 + s * C2 * Vout = Vx * (s * rb * C2 + 1) / rb
s * C1 * (V1 - Vout) + s * C2 * (Vx - Vout) = gm2 * Vx + Vout / ro2
For clarity's sake, is the following an accurate statement of the three equations?

##\qquad \textrm{Eqn 1: } V_1 = \dfrac{-g_{m_1} V_{in} + sC_1V_{out}}{g_{m_c} + sC_1}##

##\qquad \textrm{Eqn 2: } g_{m_c} V_1 + s C_2 V_{out} = V_x \dfrac{s r_b C_2 + 1}{r_b}##

##\qquad \textrm{Eqn 3: } s C_1 \left(V_1 - V_{out}\right) + s C_2 \left(V_x - V_{out}\right) = g_{m_2} V_x + \dfrac{V_{out}}{r_{o_2}}##

Thank you!
 
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e_jane said:
For clarity's sake, is the following an accurate statement of the three equations?

##\qquad \textrm{Eqn 1: } V_1 = \dfrac{-g_{m_1} V_{in} + sC_1V_{out}}{g_{m_c} + sC_1}##

##\qquad \textrm{Eqn 2: } g_{m_c} V_1 + s C_2 V_{out} = V_x \dfrac{s r_b C_2 + 1}{r_b}##

##\qquad \textrm{Eqn 3: } s C_1 \left(V_1 - V_{out}\right) + s C_2 \left(V_x - V_{out}\right) = g_{m_2} V_x + \dfrac{V_{out}}{r_{o_2}}##

Thank you!
Yes, these are the equations. Thank you very much.
 
ckt.png


I am sorry for not elaborating. The equations are obtained by KCL of the above image.
Here ##V_1##, ##V_x##, ##V_{in}## and ##V_{out}## are variables and all else are constants. I need to find the relation between ##V_{in}## and ##V_{out}##.
 
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Hi, I found the solution using the method of determinants. It was not difficult. Thanks.
 
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Debdut said:
Hi, I found the solution using the method of determinants. It was not difficult. Thanks.
If not overly long, why not write it here so others can benefit from it?
 
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