. 设集合 A={a1,a2,a3,a4} ,若集合 A 中所有三个元素的子集中的三个元素之和组...
Mar 8, 2024
. 设集合 A={a1,a2,a3,a4} ,若集合 A 中所有三个元素的子集中的三个元素之和组成的集合为 B={2,3,4,6} ,则集合 A=
Solution by Steps
step 1
To find the set A, we need to solve the system of equations given by the sums of the subsets of three elements each
step 2
The system of equations is: a1+a2+a3=2, a1+a2+a4=3, a1+a3+a4=4, a2+a3+a4=6
step 3
Solving this system of equations, we find that a1=−1, a2=1, a3=2, and a4=3
step 4
Therefore, the set A is {−1,1,2,3}
Answer
A={−1,1,2,3}
Key Concept
Solving a system of linear equations
Explanation
The solution to the system of equations represents the elements of set A such that the sums of all possible three-element subsets match the elements of set B.