-2/3x^2+6x怎么转化成二次函数y=a(x-h)^2+k_数学解答

-2/3x^2+6x怎么转化成二次函数y=a(x-h)^2+k

人气：120 ℃　时间：2020-04-01 01:03:58

解答

y=(-2/3)x^2 +6x
=(-2/3)[x^2 -9x]
=(-2/3)[x^2 -9x+(9/2)^2 -(9/2)^2]
=(-2/3)[x-(9/2)]^2 +(2/3)×(81/4)
=(-2/3)[x-(9/2)]^2 +(27/2)