³log 45 - ³log 10 + ³log 2

3 log (9 x 5 ) - 3 log 10 + 3 log 2
3 log 9 + 3 log 5 - 3log 10 + 3 log 2
2 + 3 log 5/10 + 3 log 2
2 + 3 log 1/2 + 3log 2
2 + 3 log 1/2 × 2
2 + 3 log 1
2 + 0
2