Question

1.用列举法表示下列各集合;(1)方程X的平方-3X-4=0的解集 (2)方程4X+3=0的解集(3)由数1,4,9,1

Answer 1

1、

(1){-1,4} (2) {-3/4}

(3) {1,4,9,16,25} (4) {1,3,5,7,9,……}

2.

(1) {x∣x>3,x∈R} (2) {x∣x^2-4=0,x∈R}

(3) {x∣x>5,且x=2k,x∈R,k∈Z} (4) {x∣2x-5>3,x∈R}