Advanced Search

Question: Using coeff and subs function

Question:Using coeff and subs function

ijuptilk 100 Maple
substitution subs
June 03 2023
1

I have the following code below:

eq := -((2*(alpha[3]+alpha[2]))*((1/2)*cos(Theta(z, t))^2-(1/2)*sin(Theta(z, t))^2)+(alpha[3]-alpha[2])*(sin(Theta(z, t))^2+cos(Theta(z, t))^2))*(diff(U(z, t), z))-(alpha[3]-alpha[2])*(2*sin(Theta(z, t))^2*(diff(Theta(z, t), t))+2*cos(Theta(z, t))^2*(diff(Theta(z, t), t)))+(diff(Theta(z, t), z, z))*k

simplify(subs(simplify(coeff(eq, diff(U(z, t), z))) = t1, eq))

Please, why is maple not assigning t1 to the coefficient of diff(U(z, t), z)) in the expression? 
Please Wait...