Question

已知集合{x|x²+px-2=0},且1∈A,求p的值及集合A

Answer 1

A= {x|x²+px-2=0},and 1∈A,

then

1+p-2=0

p=1#

and when p=1,

x²+x-2=0

(x+2)(x-1)=0

x= 1 or -2

A={1,-2}