sb help with a math problem!2x(square)-8x+7=y to calculate the mi_英语解答

sb help with a math problem!
2x(square)-8x+7=y to calculate the minimum and maxmum value.how?i can't graph it out.

人气：124 ℃　时间：2020-06-08 03:56:42

解答

∵y=2x^2-8x+7=2(x-2)^2-1
(x-2)^2≥0,
∴2(x-2)^2-1≥-1.
So,y(min)=-1