[求助]程序问题在哪里？

[hitzhjtopku]

a=0.03755;
g=9.8;
m=0.4387;
j1=0.25*m*a*a;
j2=j1;
j3=0.5*m*a*a;
y2=pi/12;
y3=2;
w=(-j1*sin(y2)*cos(y2));
b=((j3+m*a*a)*y3*sin(y2));
c=m*g*a*cos(y2);
y1=(-1*b+sqrt(b*b-4*w*c))/(2*w)

运行时提示为：Error: Missing variable or function.

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