matlab 求一个二元二次方程组的解

x = 2.1*v*cosa*t+0.5*w*2.1*t*t
y = 2.1*v*sina*t-0.5*85*t*t

2.1*v*cosa*t=x-0.5*w*2.1*t*t
2.1*v*sina*t=y+0.5*85*t*t

ctg(a)=(x-0.5*w*2.1*t*t)/(y+0.5*85*t*t)

t*t= (x-yctg(a))/(85ctg(a)/2+2.1*w/2)

上式大于等于0时 解得t=sqrt(t*t)

v= (x-0.5*w*2.1*t*t)/(2.1*cosa*t)

代入t计算过程 不能化简单形式，

按照上面的步骤可以计算出 t v

错了应该是这个
clc,clear;
syms x y a w
[t,v]=solve('x = 2.1*v*cosa*t+0.5*w*2.1*t*t','y = 2.1*v*sina*t-0.5*85*t*t','t','v')
>>
t =

21.0*(cosa*y - 1.0*sina*x)*(-0.045351473922902494331065759637188/((850.0*cosa + 21.0*sina*w)*(cosa*y - 1.0*sina*x)))^(1/2)
-21.0*(cosa*y - 1.0*sina*x)*(-0.045351473922902494331065759637188/((850.0*cosa + 21.0*sina*w)*(cosa*y - 1.0*sina*x)))^(1/2)

v =

-0.5*(850.0*x + 21.0*w*y)*(-0.045351473922902494331065759637188/((850.0*cosa + 21.0*sina*w)*(cosa*y - 1.0*sina*x)))^(1/2)
0.5*(850.0*x + 21.0*w*y)*(-0.045351473922902494331065759637188/((850.0*cosa + 21.0*sina*w)*(cosa*y - 1.0*sina*x)))^(1/2)

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