Question

设集合M={x|x=5-4a+a2,a∈R},N={y|y=4b24b+2,b∈R},则下M与N的关系式?

Answer 1

(1) x = 5 - 4a + a²

=a² - 4a + 4 +1

=(a -2)² + 1

因为a∈R ,所以 x > = 1 即 M={ x | x > = 1}

(2) y = 4b² + 4b +2

= 4b² + 4b + 1 +1

=(2b + 1) ² + 1

因为b∈R ,所以 y > = 1 即 N={ y| y> = 1}

综合以上得,M = N