X=(√3-√2)÷(√3﹢√2),Y=(√3+√2)÷(√3-√2),求3X²-5XY+3Y²的值.
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X=(√3-√2)÷(√3﹢√2),Y=(√3+√2)÷(√3-√2),求3X²-5XY+3Y²的值.
X=(√3-√2)÷(√3﹢√2),Y=(√3+√2)÷(√3-√2),求3X²-5XY+3Y²的值.
X=(√3-√2)÷(√3﹢√2),Y=(√3+√2)÷(√3-√2),求3X²-5XY+3Y²的值.
X=(√3-√2)÷(√3﹢√2)
=(√3-√2)²/[(√3+√2)(√3-√2)]
=5-2√6
Y=(√3+√2)÷(√3-√2)
=(√3+√2)²/[(√3-√2)(√3+√2)]
=5+2√6
3X²-5XY+3Y²
=3(x²-2xy+y²)+xy
=3(x-y)²+xy
=3×(5-2√6-5-2√6)²+(5-2√6)(5+2√6)
=3×96+25-24
=289
x=(√3-√2)÷(√3+√2)
x=(√3-√2)/(√3+√2)
x=(√3-√2)^2/[(√3+√2)(√3-√2)]
x=5-2√6
y=(√3+√2)÷(√3-√2)
y=(√3+√2)/(√3-√2)
y=(√3+√2)^2/[(√3+√2)(√3-√2)]
y=5+2√6
3x^2-5xy+3y^2
=3x^...
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x=(√3-√2)÷(√3+√2)
x=(√3-√2)/(√3+√2)
x=(√3-√2)^2/[(√3+√2)(√3-√2)]
x=5-2√6
y=(√3+√2)÷(√3-√2)
y=(√3+√2)/(√3-√2)
y=(√3+√2)^2/[(√3+√2)(√3-√2)]
y=5+2√6
3x^2-5xy+3y^2
=3x^2-6xy+3y^2+xy
=3(x^2-2xy+y^2)+xy
=3(x-y)^2+xy
=3*[5-2√6-(5+2√6)]^2+(5-2√6)(5+2√6)
=3*(5-2√6-5-2√6)^2+1
=3*(-4√6)^2+1
=288+1
=289
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