I'd be grateful if anyone could explain me the way of solving, for me it turns out to be 3 instead to 2
log(3,6)*log(9,6)+log(4,6)*log(18,6)
$$log_63*log_69+log_64*log_618\\\\
=log_63*2log_63+log_64*log_6(9*2)\\\\
=log_63*2log_63+log_64*(log_69+log_62)\\\\
=log_63*2log_63+2log_62*(2log_63+log_62)\\\\
=log_63*2log_63+4log_62log_63+2(log_62)^2\\\\
=2(log_63)^2+4log_62log_63+2(log_62)^2\\\\
=2[(log_63)^2+2log_62log_63+(log_62)^2]\\\\
=2[(log_63+log_62)^2]\\\\
=2[(log_66)^2]\\\\
=2[1^2]\\\\
=2\\$$
log(3,6)*log(9,6)+log(4,6)*log(18,6) =
log(3,6)*[log(3,6) + log(3,6)] + log(4,6)*[log(3,6) + log(3,6) + log(2,6)]
log(3,6) = ~0.613, log(4,6) = ~0.774, & log(2,6) = ~0.387.
So, 0.613*[0.613 + 0.613] + 0.774*[0.613 + 0.613 + 0.387]
= 0.752 + 1.248
= 2.
Sorry, for the re-post of Aziz's excellent answer....I was confused by the notation in this question and I wanted to get some "practice" in to make sure I understood it !!!......I'll give Aziz full credit, here!!!
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log(3)/log(6) = 0.6131471927654584
log(9)/log(6) = 1.2262943855309169
So
[log(3)/log(6)]*[log(9)/log(6)] = 0.75189895999232446469782360080696
And
log(4)/log(6) = 0.7737056144690832
log(18)/log(6) = 1.6131471927654584
So
[log(4)/log(6)]*[log(18)/log(6)] = 1.24810104000767559661689567573888
So we have
0.75189895999232446469782360080696 +1.24810104000767559661689567573888 =
2.00000000000000006131471927654584 ≈ 2
$$log_63*log_69+log_64*log_618\\\\
=log_63*2log_63+log_64*log_6(9*2)\\\\
=log_63*2log_63+log_64*(log_69+log_62)\\\\
=log_63*2log_63+2log_62*(2log_63+log_62)\\\\
=log_63*2log_63+4log_62log_63+2(log_62)^2\\\\
=2(log_63)^2+4log_62log_63+2(log_62)^2\\\\
=2[(log_63)^2+2log_62log_63+(log_62)^2]\\\\
=2[(log_63+log_62)^2]\\\\
=2[(log_66)^2]\\\\
=2[1^2]\\\\
=2\\$$