from where 12 board exam maths question are coming.that igot more than 95 and what type of book is good for maths 12 in board exam 2018

See,selective study is most usefull not only in maths but in all the subjects.In the descending order of elaboration, you can refer to the following books: RD sharma,APC publication,NCERT,NCERT exemplar..

if you are not a study geek,then RD sharma is a more than enough book.I will recomend you to do all the ‘NCERT’ and ‘CBSE 20..’and ‘EXEMPLAR’  marked questions from RD sharma.Moreover REVISION and solving past year papers and sample papers before 1 or 1½  months before the boards is a must!,,if you are successfull in doing this much,then all the marks is yours. :)