等比数列{an}中的各项均为正数,且a5a6+a4a7=18,则log3a1+log3a2+...+log3a10=由于{an}为等比数列则:a5a6=a4a7=a3a8=a2a9=a1a10又a5a6+a4a7=18则:2a5a6=18a5a6=9则:log3(a1)+log3(a2)+...+log3(a9)+log3(a10)=log3[a1*a2*a3*...*a10]=log3[(a1a
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![等比数列{an}中的各项均为正数,且a5a6+a4a7=18,则log3a1+log3a2+...+log3a10=由于{an}为等比数列则:a5a6=a4a7=a3a8=a2a9=a1a10又a5a6+a4a7=18则:2a5a6=18a5a6=9则:log3(a1)+log3(a2)+...+log3(a9)+log3(a10)=log3[a1*a2*a3*...*a10]=log3[(a1a](/uploads/image/z/12822699-3-9.jpg?t=%E7%AD%89%E6%AF%94%E6%95%B0%E5%88%97%7Ban%7D%E4%B8%AD%E7%9A%84%E5%90%84%E9%A1%B9%E5%9D%87%E4%B8%BA%E6%AD%A3%E6%95%B0%2C%E4%B8%94a5a6%2Ba4a7%3D18%2C%E5%88%99log3a1%2Blog3a2%2B...%2Blog3a10%3D%E7%94%B1%E4%BA%8E%7Ban%7D%E4%B8%BA%E7%AD%89%E6%AF%94%E6%95%B0%E5%88%97%E5%88%99%3Aa5a6%3Da4a7%3Da3a8%3Da2a9%3Da1a10%E5%8F%88a5a6%2Ba4a7%3D18%E5%88%99%3A2a5a6%3D18a5a6%3D9%E5%88%99%3Alog3%28a1%29%2Blog3%28a2%29%2B...%2Blog3%28a9%29%2Blog3%28a10%29%3Dlog3%5Ba1%2Aa2%2Aa3%2A...%2Aa10%5D%3Dlog3%5B%28a1a)
等比数列{an}中的各项均为正数,且a5a6+a4a7=18,则log3a1+log3a2+...+log3a10=由于{an}为等比数列则:a5a6=a4a7=a3a8=a2a9=a1a10又a5a6+a4a7=18则:2a5a6=18a5a6=9则:log3(a1)+log3(a2)+...+log3(a9)+log3(a10)=log3[a1*a2*a3*...*a10]=log3[(a1a
等比数列{an}中的各项均为正数,且a5a6+a4a7=18,则log3a1+log3a2+...+log3a10=
由于{an}为等比数列
则:a5a6=a4a7=a3a8=a2a9=a1a10
又a5a6+a4a7=18
则:
2a5a6=18
a5a6=9
则:
log3(a1)+log3(a2)+...+log3(a9)+log3(a10)
=log3[a1*a2*a3*...*a10]
=log3[(a1a10)*(a2a9)*...*(a5a6)]
=log3[9*9*...*9]
=log3[9^5]
=log3[3^10]
=10log3[3]
=10
但是有一步我不懂,为什么
log3(a1)+log3(a2)+...+log3(a9)+log3(a10)
=log3[a1*a2*a3*...*a10]
怎么括号里从+号变成X号了?
等比数列{an}中的各项均为正数,且a5a6+a4a7=18,则log3a1+log3a2+...+log3a10=由于{an}为等比数列则:a5a6=a4a7=a3a8=a2a9=a1a10又a5a6+a4a7=18则:2a5a6=18a5a6=9则:log3(a1)+log3(a2)+...+log3(a9)+log3(a10)=log3[a1*a2*a3*...*a10]=log3[(a1a
对数函数运算时外加等于内乘,你翻一下书,大概就在第二节左右就有