Question

设函数f(x)=x^2+(2a+1)x+a^2+3a(a属于R)，若f(x)在[0，2]上最大值为0，求a

Answer 1

当-(2a+1)/2≤1即a≥-3/2时
f(x)max=f(2)=a�0�5+7a+6=0
故a=-6(舍去),a=-1
当
-(2a+1)/2＞1，即：a＜-3/2时，f(x)max=f(0)=a�0�5+3a=0．
故a=0（舍去）或a=-3．
综上得：a的取值为：a=-1或a=-3．

Answer 2

没学过，你会了告诉我