sample.ts

function diff(arr1: number[], arr2: number[]) {
    const uniqueArr1 = arr1.filter(a1 => !arr2.includes(a1))
    const uniqueArr2 = arr2.filter(a2 => !arr1.includes(a2))
    return [...uniqueArr1, ...uniqueArr2]
}

const test1 = [[1,4,3,7],[3,4,5]]
console.log(diff(test1[0], test1[1]))

const test2 = [[1,4,3,7],[3,4,5],[5]]
console.log(test2.reduce((pre, cur) => diff(pre, cur), []))