等比数列{an}的各项均为正数,且2a1+3a2=1,a3^2=9a2a6 ⑴求数列{an﹜的通项公式由a3^2=9a2a6 可得a1^2q^4=9a1^2q^6,化简1=9q^2,又各项均为正数,q大于0,所以q=1/3.由2a1+3a2=1,可得3a1=1,a1=1/3.所以an=(1/3)^n=3^
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![等比数列{an}的各项均为正数,且2a1+3a2=1,a3^2=9a2a6 ⑴求数列{an﹜的通项公式由a3^2=9a2a6 可得a1^2q^4=9a1^2q^6,化简1=9q^2,又各项均为正数,q大于0,所以q=1/3.由2a1+3a2=1,可得3a1=1,a1=1/3.所以an=(1/3)^n=3^](/uploads/image/z/6960321-9-1.jpg?t=%E7%AD%89%E6%AF%94%E6%95%B0%E5%88%97%EF%BD%9Ban%EF%BD%9D%E7%9A%84%E5%90%84%E9%A1%B9%E5%9D%87%E4%B8%BA%E6%AD%A3%E6%95%B0%2C%E4%B8%942a1%2B3a2%3D1%2Ca3%5E2%3D9a2a6+%E2%91%B4%E6%B1%82%E6%95%B0%E5%88%97%EF%BD%9Ban%EF%B9%9C%E7%9A%84%E9%80%9A%E9%A1%B9%E5%85%AC%E5%BC%8F%E7%94%B1a3%5E2%3D9a2a6+%E5%8F%AF%E5%BE%97a1%5E2q%5E4%3D9a1%5E2q%5E6%2C%E5%8C%96%E7%AE%801%3D9q%5E2%2C%E5%8F%88%E5%90%84%E9%A1%B9%E5%9D%87%E4%B8%BA%E6%AD%A3%E6%95%B0%2Cq%E5%A4%A7%E4%BA%8E0%2C%E6%89%80%E4%BB%A5q%3D1%2F3.%E7%94%B12a1%2B3a2%3D1%2C%E5%8F%AF%E5%BE%973a1%3D1%2Ca1%3D1%2F3.%E6%89%80%E4%BB%A5an%3D%EF%BC%881%2F3%EF%BC%89%5En%3D3%5E)
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