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 PYTHON : solve symbolic,sympy,consecutive reaction A>B>C(k1,k2),version 1.0   
 peter.vlasschaert@gmail.com,07/01/2023                                        
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soln =  [Eq(A(t), a*exp(-k1*t)), Eq(B(t), a*k1*exp(-k2*t)/(k1 - k2) - a*k1*exp(-k1*t)/(k1 - k2)), Eq(C(t), -a*k1*exp(-k2*t)/(k1 - k2) + a*k2*exp(-k1*t)/(k1 - k2) + a)]
a*exp(-k1*t)
a*k1*exp(-k2*t)/(k1 - k2) - a*k1*exp(-k1*t)/(k1 - k2)
-a*k1*exp(-k2*t)/(k1 - k2) + a*k2*exp(-k1*t)/(k1 - k2) + a
=> A(t),B(t),C(t) 
A(t)= a*exp(-k1*t)
B(t)= a*k1*exp(-k2*t)/(k1 - k2) - a*k1*exp(-k1*t)/(k1 - k2)
C(t)= -a*k1*exp(-k2*t)/(k1 - k2) + a*k2*exp(-k1*t)/(k1 - k2) + a
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checkodesol((eq1,eq2,eq3), soln) = (True, [0, 0, 0])
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