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问题: 倾斜角

直线x=1+tcos(α+1.5π)(其中t为参数,0<α<π/2)的倾斜角为
y=-2+tsin(α+1.5π)
请写出详细的过程和思路,谢谢

解答:

x=1+tcos(α+1.5π)→x=1+tsinα→(x-1)/sinα=t...........(1)
y=-2+tsin(α+1.5π) →y=-2-tcosα→(y+2)/(-cosα)=t.....(2)
(其中t为参数,0<α<π/2)
化普通方程:(x-1)/sinα=(y+2)/(-cosα)→
(x-1)/(y+2)=sinα/(-cosα)→
(y+2)/(x-1)=(-cosα)/sinα→
(y+2)/(x-1)=-cotα→
(y+2)=-cotα*(x-1)→
(y+2)=tan(π/2+α)*(x-1)
∴倾斜角为θ=π/2+α