Opening Ocegik…
Skip to content
Ocegik

Ocegik / Modern Maths

Modern Maths Formulas for CAT Preparation

Revise modern maths formulas from Ocegik’s formula library, with named identities, expressions and usage notes grouped by topic.

Free to useYour progress stays yours
formulas
31
reference topics
3
in the full library
Searchable

Read the formulas by topic and check the conditions and usage notes before applying them.

Modern Maths: formulas by topic

LogarithmsModern Maths
Product ruleloga(XY) = logaX + logaYa = base, X and Y = the values being logged
Quotient ruleloga(X/Y) = logaX − logaY
Power ruleloga(Xk) = k·logaX
Root in baselogakX = 1klogaX
Root of argumentloga(ᵏ√X) = 1klogaX
Fractional-power baseloga1/kX = k·logaX
Identity of 1loga1 = 0
Same base identitylogxX = 1
Reciprocal base swaplogaX = 1logXa
Change of baselogaX = logbXlogba
Exponent inversea(logaX) = X
Default base conventionunmentioned base is taken as 10
Permutations & CombinationsModern Maths
PermutationsnPr = n!(n − r)!
CombinationsnCr = n!(n − r)! r!
Combination–permutation linknCr = nPrr!
Symmetry of combinationsnCr = nCn−r
Sum of all combinationsnC0 + nC1 + … + nCn = 2n
Distributing n identical items among r personsn+r−1Cr−1
Permutations with repeated itemsn!p! q! r!p, q, r items of each repeated kind
Selections from grouped items{(p+1)(q+1)(r+1)…} − 1selecting some or all from p items of one type, q of another, r of another…
Circular arrangements(n − 1)!
Dividing (m+n) things into groups of m, n(m + n)!m! n!
Dividing 2m things into two equal groups(2m)!2!(m!)2
ProbabilityModern Maths
Probability of an eventP(E) = favourable outcomesall possible outcomesP(E) = probability that event E occurs
Complement ruleP(not E) = 1 − P(E)
Odds in favour= favourable cases / unfavourable cases
Odds against= unfavourable cases / favourable cases
Addition Law (general)P(A or B) = P(A) + P(B) − P(A ∩ B)
Addition Law (mutually exclusive)P(A ∩ B) = 0
Independent eventsP(A ∩ B) = P(A) × P(B)
Multiplication LawP(E and F) = P(E) × P(F)E, F independent

Keep your preparation connected

Your next step, in one place.

Bring your practice, mock reviews and study plan together.

Browse Mock Library