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

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

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

(1)大于等于-9
(2)全体实数