第1121题:直线的点斜式方程
一条直线经过点(3,23)(3,2\sqrt{3})(3,2√3) ,其倾斜角是 30°30\degree30° ,则此直线的点斜式(point slope form)是( ).
A. y−23=y-2\sqrt{3}=y−2√3=33(x−3) \dfrac{\sqrt{3}}{3}(x-3)3√3(x−3)
B. y=33xy=\dfrac{\sqrt{3}}{3}xy=3√3x +3+\sqrt{3}+√3
C.y−33x y-\dfrac{\sqrt{3}}{3}xy−3√3x −3=0 -\sqrt{3} =0−√3=0
D. 3y=3x+333y=\sqrt{3}x+3\sqrt{3}3y=√3x+3√3