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
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