求值域,(1)y=2x平方+4x-7/(x+1)平方+2 (2)y=5x-1/4x+2

问题描述:

求值域,(1)y=2x平方+4x-7/(x+1)平方+2 (2)y=5x-1/4x+2

y=2x平方+4x-7/(x+1)平方+2
=2(x+1)^2-9/(x+1)平方+2
=2- 13/(x+1)平方+2
>=-5/4
y=5x-1/4x+2
x≠-1/2