- Prime Number - (1 to 25 = 9, 25 to 50 = 6, 50 to 75 = 6, 75 to 100 =4 , 1 to 100 = 25, 1 to 200 =46 , 100 to 200 = 21 , 200 to 300 = 16 )
- all prime no. ko ( 6k+_1 ) ke form me likh sakte hai .
- Prime Test : wah sankhya 2,3 and 5 se vibhajy hai ki nahi.
- number/6 - remendar - 1/5 bache to vah prime number ho sakti hai .
- co-prime ' vah sankhya jiska dono sankhya abhajy ho . jaise :- ( 3,2) , (5,11) , (7,5) , ( 11,13 ) , (19,23)
- sapekshit yaa aapekshi abhajy sankya : us sankhya ko kahenge jiska hcf 1 ho . jaise ( 2,3), (7,9) , (8,9 ) , (12,13)
- Twin Prime No.( judwa abhajy sankhya ) : jo dono abhajy ho tatha dono ke beech do ka antar ho ; example : (5,7) , (11,13) , (17,19)
- 1 to 100 tak kul 8 jode judwa abhajy sankhya hai . (3,5) , (5,7), (11,13), (17,19), 29,31),(41,43) , (59,61) , (71,73)
- Rational No ( Parimey Sankhya ) : jise p/q ke rup me likh sakte hai . p,q- purnak ho ,
- irrational number ( aparimey sankhya ) : jise p/q ke rup me naa likha jaye . jaise : ashant dashmalav ( non- terminating Decimal , Non- Repeating Decimal ( ashant anavarti dashmalv ) [paai ,root 3, root 5.
- 3,4,5.,6,
- parallelogram rule ; d1
