已知二次函数f(x)=x²-2x-n²-n的图像与x轴的交点为(an,0)、(bn,0)(n=1,2,3…n是下标)则式子1/a1+1/a2+…+1/a2008+1/b1+1/b2+…+1/b2008=
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![已知二次函数f(x)=x²-2x-n²-n的图像与x轴的交点为(an,0)、(bn,0)(n=1,2,3…n是下标)则式子1/a1+1/a2+…+1/a2008+1/b1+1/b2+…+1/b2008=](/uploads/image/z/11699832-48-2.jpg?t=%E5%B7%B2%E7%9F%A5%E4%BA%8C%E6%AC%A1%E5%87%BD%E6%95%B0f%28x%29%3Dx%26%23178%3B-2x-n%26%23178%3B-n%E7%9A%84%E5%9B%BE%E5%83%8F%E4%B8%8Ex%E8%BD%B4%E7%9A%84%E4%BA%A4%E7%82%B9%E4%B8%BA%EF%BC%88an%2C0%EF%BC%89%E3%80%81%28bn%2C0%29%28n%3D1%2C2%2C3%E2%80%A6n%E6%98%AF%E4%B8%8B%E6%A0%87%EF%BC%89%E5%88%99%E5%BC%8F%E5%AD%901%2Fa1%2B1%2Fa2%2B%E2%80%A6%2B1%2Fa2008%2B1%2Fb1%2B1%2Fb2%2B%E2%80%A6%2B1%2Fb2008%3D)
已知二次函数f(x)=x²-2x-n²-n的图像与x轴的交点为(an,0)、(bn,0)(n=1,2,3…n是下标)则式子1/a1+1/a2+…+1/a2008+1/b1+1/b2+…+1/b2008=
已知二次函数f(x)=x²-2x-n²-n的图像与x轴的交点为(an,0)、(bn,0)(n=1,2,3…n是下标)
则式子1/a1+1/a2+…+1/a2008+1/b1+1/b2+…+1/b2008=
已知二次函数f(x)=x²-2x-n²-n的图像与x轴的交点为(an,0)、(bn,0)(n=1,2,3…n是下标)则式子1/a1+1/a2+…+1/a2008+1/b1+1/b2+…+1/b2008=
f(x) = (x-1)^2 - (n+1/2)^2 - 3/4
an = 1 + 根号(.)
bn = 1 - 根号(.)
an+bn = 2
an*bn = n^2 + n=n(n+1)
1/a1+1/b1 + . + 1/a2008 + 1/b2009 = 2 (1/2 + 1/6 + ...+ 1/(2008*2009)) = 2 (1 - 1/2009) = 4016/2009