lg2 lg5+lg2+(lg5)? +2
=[lg2 lg5+(lg5)? ]+lg2+2
=lg5(lg2+lg5)+lg2+2
=lg5+lg2+2
= 1+2
=3
Solution 2:
=lg( 10/5) lg5+lg2+(lg5)? +2
=( 1-lg5) lg5+lg2+(lg5)? +2
=lg5-(lg5)? +lg2+(lg5)? +2