一道数学题
分母有理化
x=(√3-√2)(√3-√2)/(3-2)
=(3-2√6+2)/1
=5-2√6
y=(√3+√2)(√3+√2)/(3-2)
=(3+2√6+2)/1
=5+2√6
x²-y²=(5-2√6)²+(5+2√6)²
=(5-2√6+5+2√6)-2(5-2√6)(5+2√6)
=10²-2(25-4×6)
=100-2
=98
=
化简得:
x²=1/(5+2√6)
y²=1/(5-2√6)
x²+y²=1/(5+2√6)+1/(5-2√6)=(5-2√6+5+2√6)/(25-24)=10
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