求由参数方程x=1-t*2 y=t-t*3 的微分-搜答案-神马作文网

不是很简单吗?x=根号2t-1移项得1+x=根号2t,y=二分之根号二t两边同乘2得2y=根号2t,所以有1+x=2y,就是直角坐标方程

x^2/4+y^2/16=0所以x=2cosθy=4sinθ

x=y^2-y-2再问：求解答过程再答：y=t-1,t=y+1,代入，x=(y+1)^2-3(y+1)+1=y^2+2y+1-3y-3+1=y^2-y-1检验的时候发现上面回答的错了，答案是y^2-y

由参数方程消去参数t就可以了.由x=1+2t得到t=(x-1)/2把它代入y=t^2中：y=[(x-1)/2]^2=(x^2-2x+1)/4即：x^2-2x-4y+1=0

dx/dt=-2tdy/dt=1-2tdy/dx=(dy/dt)/(dx/dt)=(1-2t)/(-2t)=-1/(2t)+1

dy/dx=(dy/dt)/(dx/dt)=[2t/(1+t^2)]/[1-1/(1+t^2)]=2/t

1.(1)dy/dx=(dy/dt)/(dx/dt)=2t/2=t=x/2(2)dy/dx=(dy/dt)/(dx/dt)=e^t/(e^-t-te^-t)=y/(1/y-x)=y^2/(1-xy)2

x-1=(t+1)/(t-1)-1=2/(t-1)t-1=2/(x-1)t=(x+1)/(x-1)t^2+t+1=(x+1)^2/(x-1)^2+(x+1)/(x-1)+1=(3x^2+1)/(x-1

x=arcsint;y=sqrt(1-t^2)所以dy/dx=(dy/dt)/(dx/dt)=（-2t/sqrt(1-t^2)）/(1/sqrt(1-t^2))=-t=-sinx所以d^2y/dx^2

dy/dt=cost-cost+tsint=tsintdx/dt=-sintdy/dx=(dy/dt)/(dx/dt)=-t再问：为什么-tcost会分解成-cost+tsint~~~+_+知道了==

dx=(1+lnt)dtdy=(t+2tlnt)dt∴dy/dx=(t+2tlnt)/(1+lnt)……（1）有原参数方程可以得到t=y/x,lnt=x^2/y代入（1）中即可得到答案.自己代吧我做的

由y=t³+2t得：dy/dt=3t^2+2由x-eˆxsint+1=0得：1-(e^xsint+e^xcostdt/dx)=0得：dt/dx=(1-e^xsint)/e^xcos

X=t+1/tY=t-1/t都平方得X^2=t^2+2+1/t^2,Y^2=t^2-2+1/t^2X^2-Y^2=4

-4t=2x-6=y+12x-y-7=0

2x-y+1=0再问：有木有过程谢谢QAQ再答：直接把t=x代入第二个方程就可以得到了啊

x=t+1/ty=t-1/t两式相加得：t=(x+y)/2代入其中1式得：x=(x+y)/2+2/(x+y)化为：x^2-y^2=4此为双曲线.

dy/dx=(dy/dt)/(dx/dt)dy/dt=-4t^3dx/dt=e^t+(t-1)e^t=te^t所以dy/dx=-4t^2/e^t

dx=1/(1+t^2)*dt,dy=2t/(1+t^2)*dt,所以切线斜率为k=dy/dx=2t|(t=1)=2,又切点坐标为x=arctan1=π/4,y=ln(1+1)=ln2,所以切线方程为

dx/dt=-2tdy/dt=1-3t^2dy/dx=(dy/dt)/(dx/dt)=(1-3t^2)/(-2t)

dx/dt=2[(1+t^2-2t^2]/(t+t^2)^2=2(1-t^2)/(1+t^2)^2dy/dt=[-2t(1+t^2)-(1-t^2)*2t]/(1+t^2)^2=-4t/(1+t^2)