/a-a/b
=(b²-a²)/ab
=[1/(2-根号3)²-1/(2+根号3)²]/[1/(2+根号3)(2-根号3)]
=[1/(7-4根号3)-1/(7+4根号3)]×(2+根号3)(2-根号3)
=[(7+4根号3)-(7-4根号3)]/[(7+4根号3)(7-4根号3)] ×(4-3)
=[8根号3/(49-48)]×1
=8根号3
/a-a/b
=(b²-a²)/ab
=[1/(2-根号3)²-1/(2+根号3)²]/[1/(2+根号3)(2-根号3)]
=[1/(7-4根号3)-1/(7+4根号3)]×(2+根号3)(2-根号3)
=[(7+4根号3)-(7-4根号3)]/[(7+4根号3)(7-4根号3)] ×(4-3)
=[8根号3/(49-48)]×1
=8根号3