原式=(√2+√3-√5)/(√2+√3+√5)(√2+√3-√5)
=(√2+√3-√5)/[(√2+√3)²-(√5)²]
=(√2+√3-√5)/(5+2√6-5)
=(√2+√3-√5)/2√6
=√6(√2+√3-√5)/12
=(2√3+3√2-√30)/12
分母有理化,分子和分母都乘以(√2+√3-√5)
1/(√2+√3+√5)=(√2+√3-√5)/[(√2+√3)^2-(√5)^2]
=(√2+√3-√5)/2√6
=(2√3+3√2-√30)/12
1/(√2+√3+√5)
=(√2+√3-√5)/[(√2+√3+√5)(√2+√3-√5)]
=(√2+√3-√5)/(2+2√6+3-5)
=(√2+√3-√5)/2√6
=√6*(√2+√3-√5)/12
=(2√3+3√2-√30)/12
0.1857930606
第二个等于-0.5960780949
0.1858