A=Q/V=18.667
A=(b+y)y=18.667 , by+y^2=18.667............(1)
P=y+ ((m^2+1^2)^0.5 )*y+b ,m=2
P=y+(根號5)y+b
L(y,b,λ)=(1+根號5)y+b+λ(by+y^2-18.667)
L(y,b,λ) 對y偏微分 =(1+根號5)+λ(b+2y)=0
L(y,b,λ) 對b偏微分 =1+λ(y)=0
λ=-(1+根號5)/(b+2y)= (-1)/(y)
解得1.236y=b
帶回 (1) 1.236y^2+y^2=18.667
y=2.889 b=3.570
帶回Q=1/n *A*R^(2/3) *S0^(0.5)
解得s0=2.7*10^(-4)