∵f(x)=2ax2+2x-3-a=0在[-1,1]上有解,∴(2x2-1)a=3-2x在[-1,1]上有解
∴
1 |
a |
2x2-1 |
3-2x |
问题转化为求函数y=
2x2-1 |
3-2x |
设t=3-2x,x∈[-1,1],则2x=3-t,t∈[1,5],
∴y=
1 |
2 |
7 |
t |
设 g(t)=t+
7 |
t |
7 |
t2 |
7 |
t∈(
7 |
∴y的取值范围是[
7 |
∴
1 |
a |
7 |
∴a≥1或a≤
-3-
| ||
2 |
故答案为(-∞,
-3-
| ||
2 |
1 |
a |
2x2-1 |
3-2x |
2x2-1 |
3-2x |
1 |
2 |
7 |
t |
7 |
t |
7 |
t2 |
7 |
7 |
7 |
1 |
a |
7 |
-3-
| ||
2 |
-3-
| ||
2 |