Question

Answer 1

13:

x^2<=4

=>x^2-4<=0

=>(x-2)(x+2)<=0

=>-2<=x<=2

(2x^2-3x)(x^2-x-6)=0

=>x(2x-3)(x-3)(x+2)=0

=>\(x\in\left\{0;\dfrac{3}{2};3;-2\right\}\)

A={x thuộc Z;z^2<=4}

=>A={0;1;-1;2;-2}

B={x thuộc Z|(2x^2-3x)(x^2-x-6)=0}

=>B={0;3;-2}

(A hợp B)\(A giao B)

={0;1;-1;2;-2;3}\{0;-2}

={1;-1;2;3}