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问题: 高中数学

高中数学求值X/Y=?,其中:
X=(2^4+1/4)*(4^4+1/4)*(6^4+1/4)*(8^2+1/4)*(10^4+1/4),
Y=(1^4+1/4)*(3^4+1/4)*(5^4+1/4)*(7^2+1/4)*(9^4+1/4),

解答:

高中数学 求值X/Y=?,其中:
X=(2^4+1/4)*(4^4+1/4)*(6^4+1/4)*(8^4+1/4)*(10^4+1/4),
Y=(1^4+1/4)*(3^4+1/4)*(5^4+1/4)*(7^4+1/4)*(9^4+1/4),

解 16(n^4+1/4)=4(4n^4+1)
=4[(2n^2+1)^2-4n^2]=4(2n^2+2n+1)*(2n^2-2n+1)
=[(2n+1)^2+1]*[(2n-1)^2+1]
=[(2n+1)^2+1][(2n-1)^2+1]
所以更一般式: X/Y=[(2n+1)^2+1]/[1^4+1]
故X/Y=[21^2+1]/[1^2+1]=221.