已知函数y=根号2+x-x2的定义域为A,函数y=a-2x-x2,x属于[-2,1]的值域为B,全集U=R,(CuA)∪B=R,求实数a的取值范围

[-2,1]上,y=a-2x-x^2=a+1-(x+1)^2 取值范围 [a-3,a+1] 即 B=[a-3,a+1]y=√2+x-x^2=√9/4-(x-1/2)^2 定义域应满足 9/4-(x-1/2)^2≥0 |(x-1/2)|≤3/21/2-3/2≤x≤1/2+3/2 即 A=[-1,2]要使(CuA)∪B=R,应有:a-32 得1...