_ log18 (Sx9) _ log18S+log189 _ a+b a + b a+b\r: . tog3645 = 18 =\r—-log18 36 log18 (4X9) = 2log18 2+log19 9 = 2log18'7+log18 9 2-2log18 9+ log1,8 9 2- a\r9\r跟踪训练 3 解析 ： (l )lg5= log65 = q = q\rlog610 log6 2+log6 5 p+q·\r(2)(D'.'log147 = a, 141>=5,\r: . b = log145.\r,142\r••• log3528 ＝竺芒＝ lo g吓\rlog1435 log14 ( 5x7)\r= log14142-log14 7 =_ 2-a\rlog14 S+log14 7 a+b·\r@ ? 3x=36 ，心＝ 36,\r:. x= log336, y= log436,\r• 1 1 1\r.. - = =~=log363 ,\rx log3 36 log36 36\rlog36 3\r1 1 1\r-=—=-—= log364,\ry log436 ~\rlog364\r• 2 , 1\r:.::+~=21og363 + log364=Jog36(9 X4)= l.\rX y\r答案： (1~ (2)。仁巴 @l\rp +q a+b
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