√2(1-√2)
=√2×1-√2×√2
=√2-2
(√32-√72)-(√300+2√48)
=√32-√72-√300-2√48
=4√2-6√2-10√3-2×4√3
=-2√2-10√3-8√3
=-2√2-18√3
(1-√3)²
=1²-2×1×√3+√3²
=1-2√3+3
=4-2√3
(√54+1/3×√27)÷√3
=√54÷√3+1/3×√27÷√3
=√(54÷3)+1/3×√(27÷3)
=√18+1/3×√9
=3√2+1/3×3
=3√2+1
(2√3-3)(√2+√3)
=2√3×√2+2√3×√3-3×√2-3×√3
=2√(3×2)+2×3-3√2-3√3
=2√6+6-3√2-3√3
(2√x-√y)(√x+2√y)
=2√x×√x+2√x×2√y-√y×√x-√y×2√y
=2x+4√xy-√xy-2y
=2x-3√xy-2y
(2√6-1)(5√2+√3)
=2√6×5√2+2√6×√3-1×5√2-1×√3
=10√12+2√18-5√2-√3
=10×2√3+2×3√2-5√2-√3
=20√3+6√2-5√2-√3
=19√3-√2
(√3-√2)^2006×(√3+√2)^2007 ( ^ 表示乘方)
=(√3-√2)^2006×(√3+√2)^2006×(√3+√2)
=[(√3-√2)(√3+√2)]^2006×(√3+√2)
=(√3²-√2²)^2006×(√3+√2)
=(3-2)^2006×(√3+√2)
=1^2006×(√3+√2)
=√3+√2