解:∵x=2+根号3 y=2-根号3
∵x平方-y的平方=(X+Y)(X-Y)
∴x平方-y的平方=﹙2+根号3+2-根号3 ﹚[2+根号3-﹙2-根号3 ﹚]
=4×2√3
=8√3
x^2-y^2
=(x+y)(x-y)
=(2+√3+2-√3)(2+√3-2+√3)
=4*2√3
=8√3
x平方-y的平方
=x²-y²
=(x+y)*(x-y)
=4*(2√3)
=8√3
解:x²-y²=(x-y)²+2xy
=(2+根号3-2+根号3)²+2×1
= 12+2
=14
x平方-y的平方=﹙x+y﹚﹙x--y﹚﹚=8√3
(x+y)(x-y)=8√3