matlab求解有root,Matlab 高次参数方程求解出现root

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[backcolor=rgb(242, 242, 242)][size=12px][color=#999999]>> syms D_d1 D_d2 D_r1 D_r2 P_d1 P_d2 P_r1 P_r2 S_d S_r q q_1 R r D E F G H I J K L M N O P[/color][/size][/backcolor]

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y2 =[size=14px](E + D*(q + (M + L*q_1)/(N*q_1^2 + O*q_1 + P) - (2*S_d*(K + J*q_1 + I*q_1^2 - (M + L*q_1)/(N*q_1^2 + O*q_1 + P)))/(2*S_d - 2*S_r)))*((S_d*(J + 2*I*q_1 - L/(N*q_1^2 + O*q_1 + P) + ((M + L*q_1)*(O + 2*N*q_1))/(P + O*q_1 + N*q_1^2)^2))/(2*S_d - 2*S_r) - L/(2*(N*q_1^2 + O*q_1 + P)) + ((M + L*q_1)*(O + 2*N*q_1))/(2*(P + O*q_1 + N*q_1^2)^2) + 1) - E*((S_d*(J + 2*I*q_1 - L/(N*q_1^2 + O*q_1 + P) + ((M + L*q_1)*(O + 2*N*q_1))/(P + O*q_1 + N*q_1^2)^2))/(2*S_d - 2*S_r) - L/(2*(N*q_1^2 + O*q_1 + P)) + ((M + L*q_1)*(O + 2*N*q_1))/(2*(P + O*q_1 + N*q_1^2)^2)) - D*(2*(q/2 - q_1 + (M + L*q_1)/(2*(N*q_1^2 + O*q_1 + P)) - (S_d*(K + J*q_1 + I*q_1^2 - (M + L*q_1)/(N*q_1^2 + O*q_1 + P)))/(2*S_d - 2*S_r))*((S_d*(J + 2*I*q_1 - L/(N*q_1^2 + O*q_1 + P) + ((M + L*q_1)*(O + 2*N*q_1))/(P + O*q_1 + N*q_1^2)^2))/(2*S_d - 2*S_r) - L/(2*(N*q_1^2 + O*q_1 + P)) + ((M + L*q_1)*(O + 2*N*q_1))/(2*(P + O*q_1 + N*q_1^2)^2) + 1) + ((q - (S_d*(I*q_1^2 + J*q_1 + K))/(S_d - S_r) + (S_r*(M + L*q_1))/((S_d - S_r)*(N*q_1^2 + O*q_1 + P)))*((S_d*(J + 2*I*q_1))/(S_d - S_r) - (L*S_r)/((S_d - S_r)*(N*q_1^2 + O*q_1 + P)) + (S_r*(M + L*q_1)*(O + 2*N*q_1))/((S_d - S_r)*(P + O*q_1 + N*q_1^2)^2)))/6) + D*((2*S_d*(J + 2*I*q_1 - L/(N*q_1^2 + O*q_1 + P) + ((M + L*q_1)*(O + 2*N*q_1))/(P + O*q_1 + N*q_1^2)^2))/(2*S_d - 2*S_r) - L/(N*q_1^2 + O*q_1 + P) + ((M + L*q_1)*(O + 2*N*q_1))/(P + O*q_1 + N*q_1^2)^2)*(q/2 - q_1 + (M + L*q_1)/(2*(N*q_1^2 + O*q_1 + P)) - (S_d*(K + J*q_1 + I*q_1^2 - (M + L*q_1)/(N*q_1^2 + O*q_1 + P)))/(2*S_d - 2*S_r)) - 2*D*(q/2 + (M + L*q_1)/(2*(N*q_1^2 + O*q_1 + P)) - (S_d*(K + J*q_1 + I*q_1^2 - (M + L*q_1)/(N*q_1^2 + O*q_1 + P)))/(2*S_d - 2*S_r))*((S_d*(J + 2*I*q_1 - L/(N*q_1^2 + O*q_1 + P) + ((M + L*q_1)*(O + 2*N*q_1))/(P + O*q_1 + N*q_1^2)^2))/(2*S_d - 2*S_r) - L/(2*(N*q_1^2 + O*q_1 + P)) + ((M + L*q_1)*(O + 2*N*q_1))/(2*(P + O*q_1 + N*q_1^2)^2))[/size]

>> solve(y2,q_1)

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