CDS Syllabus 2020: The “Combined Defence Services” (CDS) Examination is conducted twice a year by the Union Public Service Commission for recruitment into the Indian Military Academy, Officers Training Academy, Indian Naval Academy and Indian Air Force Academy. The Notification for the examination is usually released in the months of October/November and June/July, and the examinations are conducted in February and November respectively. Only unmarried graduates are eligible to sit for the exam. Successful candidates are admitted into the respective Academies after an interview conducted by the Services Selection Board (SSB). To clear the examination, first, you need is the complete information of the pattern, syllabus and previous year exam analysis so that it would become easy for you to analyse the examination and to prepare a strategy further.
CDS Syllabus 2020: Overview
Mode of exam 
Offline 
Number of sections 
Indian Military Academy (IMA), Indian Naval Academy (INA) and Air Force Academy (AFA) – Three
Officers’ Training Academy (OTA) – Two 
Total marks of the test 
IMA, INA and AFA – 300
OTA – 200 
Nature of questions 
Objective type 
Language of question paper 
Hindi and English 
Duration of the test 
2 hours for each section of test 
CDS Syllabus 2020: Exam Pattern for IMA, INA, AFA
Subject 
Duration 
Maximum marks 
English 
2 hours 
100 
General Knowledge 
2 hours 
100 
Elementary Mathematics 
2 hours 
100 
CDS Syllabus 2020: Exam Pattern for OTA
Subject 
Duration 
Maximum marks 
English 
2 hours 
100 
General Knowledge 
2 hours 
100 
CDS Syllabus 2020: Marking Scheme
Negative marking is applicable for every wrong marked answer. In CDS paper, each question carries 4 options and out of which only 1 option is correct. For each incorrect answer, 1/3 of the marks will be deducted. More than one option marked is treated as incorrect. However, if a question is left unanswered there will be no negative marking.
CDS Syllabus 2020: SubjectWise Syllabus
Candidates can check the UPSC CDS Syllabus in the table given below.
Sections 
Topics 
English 
 Spotting Errors Questions
 Sentence Arrangement Questions
 Synonyms & Antonyms
 Selecting Words
 Ordering of Sentence
 Comprehension Questions
 Ordering of words in a sentence
 Fill in the blanks questions
 Idioms and Phrases

General Awareness 
 Economics
 Physics
 Current Awareness
 Politics
 Chemistry
 Sociology
 History
 Defence related Award
 Geography
 Environment
 Sport
 Biology
 Cultural
 Book
 Statement
 true/false

Elementary Mathematics 
Algebra 
 Basic Operations
 simple factors
 Remainder Theorem
 H.C.F.
 L.C.M.
 Theory of polynomials
 solutions of quadratic equations
 relation between its roots and coefficients (Only real roots to be considered)
 Simultaneous linear equations in two unknowns—analytical and graphical solutions
 Simultaneous linear inequations in two variables and their solutions
 Practical problems leading to two simultaneous linear equations or inequations in two variables or quadratic equations in one variable & their solutions
 Set language and set notation
 Rational expressions and conditional identities
 Laws of indices

Arithematic 
 Number System: Natural numbers, Integers, Rational and Real numbers.
 Fundamental operations: addition, substraction, multiplication, division, Square roots, Decimal fractions
 Unitary method
 time and distance
 time and work
 percentages
 applications to simple and compound interest
 profit and loss
 ratio and proportion
 variation
 Elementary Number Theory: Division algorithm
 Prime and composite numbers
 Tests of divisibility by 2, 3, 4, 5, 9 and 11
 Multiples and factors. Factorisation Theorem
 H.C.F. and L.C.M.
 Euclidean algorithm
 Logarithms to base 10
 laws of logarithms
 use of logarithmic tables

Trigonometry 
 Sine ×, cosine ×, Tangent × when 0° < × < 90°
 Values of sin ×, cos × and tan ×, for ×= 0°, 30°, 45°, 60° and 90°
 Simple trigonometric identities
 Use of trigonometric tables
 Simple cases of heights and distances

Geometry 
 Lines and angles
 Plane and plane figures
 Theorems on Properties of angles at a point
 Parallel lines
 Sides and angles of a triangle
 Congruency of triangles
 Similar triangles
 Concurrence of medians and altitudes
 Properties of angles
 sides and diagonals of a Parallelogram
 rectangle and square
 Circles and its properties including tangents and normals
 Loci

Mensuration 
 Areas of squares
 rectangles
 parallelograms
 triangle and circle
 Areas of figures which can be split up into these figures (Field Book)
 Surface area and volume of cuboids
 lateral surface and volume of right circular cones and cylinders
 surface area and volume of spheres

Statistics 
 Collection and tabulation of statistical data
 Graphical representation frequency polygons
 histograms
 bar charts
 pie charts etc
 Measures of central tendency

CDS Syllabus 2020: FAQs
Q 1. How many stages CDS exam have?
Ans. There are only two stages, written exam and SSB exam
Q 2. Does CDS OTA and CDS IMA have different exam?
Ans. Yes, OTA and IMA have different exam with different sections.
Q 3. Is there any negative marking in the CDS?
Ans. Yes, there is a negative marking in prelims of 1/3 marks.
Q 4. How many sections CDS IMA paper have?
Ans. There are 3 sections in CDS IMA paper.
Q 5. How many sections CDS OTA paper have?
Ans. There are only 2 sections in CDS OTA paper.
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