- 数学问答二解答问题g
- 问答二解答问题 g
- 解：(1)
|f(0)|≤1,即知|c|≤1
|f(1)|=|a+b+c|≤1
|f(0.5)|=|0.25a+0.5b+c|≤1
凑一下
0.5|a|=|a+b+c-2(0.25a+0.5b+c)+c|
≤|f(1)|+2|f(0.5)|+|f(0)|≤4
故|a|≤8
|b|=|a+b+c-4(0.25a+0.5b+c)+3c|
≤|f(1)|+4|f(0.5)|+3|f(0)|≤8
故|b|≤8
故|a|+|b|+|c|≤17
(2)y=8x^2-8x+1