Question

已知函数f(x)=ax-(3/2)*x^2的最大值不大于1/6,有当x∈[1/4,1/2]时,f(x)≧1/8,求a的值

Answer 1

f(x)=ax-(3/2)*x^2

=(-3/2)(x-a/3)^2+a^2/6

fmax(x)=f(a/3)=a^2/6