函数表达式y=-9(x-2)²+1当y=0时,如何得算出与x轴的交点坐标为(7/3,0),(5/3,0).还有,一元二次方程怎么算?举下例子.
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![函数表达式y=-9(x-2)²+1当y=0时,如何得算出与x轴的交点坐标为(7/3,0),(5/3,0).还有,一元二次方程怎么算?举下例子.](/uploads/image/z/2212919-71-9.jpg?t=%E5%87%BD%E6%95%B0%E8%A1%A8%E8%BE%BE%E5%BC%8Fy%3D-9%28x-2%29%26%23178%3B%2B1%E5%BD%93y%3D0%E6%97%B6%2C%E5%A6%82%E4%BD%95%E5%BE%97%E7%AE%97%E5%87%BA%E4%B8%8Ex%E8%BD%B4%E7%9A%84%E4%BA%A4%E7%82%B9%E5%9D%90%E6%A0%87%E4%B8%BA%EF%BC%887%2F3%2C0%EF%BC%89%2C%285%2F3%2C0%29.%E8%BF%98%E6%9C%89%2C%E4%B8%80%E5%85%83%E4%BA%8C%E6%AC%A1%E6%96%B9%E7%A8%8B%E6%80%8E%E4%B9%88%E7%AE%97%3F%E4%B8%BE%E4%B8%8B%E4%BE%8B%E5%AD%90.)
函数表达式y=-9(x-2)²+1当y=0时,如何得算出与x轴的交点坐标为(7/3,0),(5/3,0).还有,一元二次方程怎么算?举下例子.
函数表达式y=-9(x-2)²+1
当y=0时,如何得算出与x轴的交点坐标为(7/3,0),(5/3,0).还有,一元二次方程怎么算?举下例子.
函数表达式y=-9(x-2)²+1当y=0时,如何得算出与x轴的交点坐标为(7/3,0),(5/3,0).还有,一元二次方程怎么算?举下例子.
解y=-9(x-2)^2+1
故当y=0时,
-9(x-2)^2+1=0
即(x-2)^2=1/9
开平方得
x-2=1/3或x-2=-1/3
解得x=7/3或x=5/3
故x=5/3时,y=-9(x-2)^2+1=0,即函数图像过点(5/3,0),
x=7/3时,y=-9(x-2)^2+1=0,即函数图像过点(7/3,0),
故函数图像与x轴的交点坐标为(7/3,0),(5/3,0).
当Y=0时,有-9(x-2)^2+1=0,(x-2)^2=1/9,开方x-2=1/3或x-2=-1/3故x=7/3或x=5/3