已知抛物线y=六分之一(X-2)(x-2t-3)(t大于0)与X轴交于点A,B(在A的左边)与y轴交与点C
问题描述:
已知抛物线y=六分之一(X-2)(x-2t-3)(t大于0)与X轴交于点A,B(在A的左边)与y轴交与点C
求:(1)求A,B,C各点的坐标(可用含t的代数式表示)
(2)设△ABC的面积为2分之21,求抛物线的解析式
要速度
答
(1)y= (1/6)(x-2)(x-2t-3)y =0=> x= 2 or 2t+3A(2t+3,0),B(2,0)x=0y=(1/6)(-2)(-2t-3)=(1/3)(2t+3)C(0,(1/3)(2t+3))(2)|AB| = 2t+1|OC| = (1/3)(2t+3) △ABC的面积= 21/2 = (1/2)|AB||OC|=>21/2 = (1/6)(2t+3)(2t+1)...