Given,
⇒3log 2−31log 27+log 12−log 4+3log 5⇒log 23−log 2731+log 12−log 4+log 53⇒log 8−log 327+log 12−log 4+log 125⇒log 8−log 3+log 12−log 4+log 125⇒log 8+log 12+log 125−log 4−log 3⇒(log 8+log 12+log 125)−(log 4+log 3)⇒log (8×12×125)−log (4×3)⇒log (12000)−log (12)⇒log (1212000)⇒log 1000⇒log 103⇒3log 10⇒3×1⇒3.
Hence, 3log 2−31log 27+log 12−log 4+3log 5 = 3.