The function f (x) is even and is a decreasing function on (- ∞ 0). Try to compare the size of F (- 7 / 8) and f (2a & # 178; - A + 1)

The function f (x) is even and is a decreasing function on (- ∞ 0). Try to compare the size of F (- 7 / 8) and f (2a & # 178; - A + 1)

2a²-a+1=2(a-1/4)^2+1-1/8=2(a-1/4)^2-7/8>=-7/8
So f (- 7 / 8)