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Grade 12 Technical Mathematics: modules and lessons

Explore Grade 12 Technical Mathematics: 10 modules and 80 lesson entries. Use the dorKk lesson guide to plan revision and catch-up study.

dorKk provides pre-recorded CAPS-aligned video lessons for self-paced study alongside schoolwork. Choose a module below, find the lesson that matches your classwork, and use the sequence to identify gaps. This guide lists lesson titles; access to the videos depends on your subscription. dorKk is not an online school.

Source: dorKk English lesson list dated 21 January 2026. Catalogue entries may differ from current app availability.

Plan your study

  1. Choose the module you are currently studying at school.
  2. Try a textbook question first and note where you get stuck.
  3. Watch the matching lesson, try again and keep a list of questions for your teacher.

COMPLEX NUMBERS

  1. 1.1.COMPLEX NUMBER; IMAGINARY NUMBERS AND CONJUGATES
  2. 1.2.ADD; SUBTRACT; MULTIPLY OR DIVIDE COMPLEX NUMBERS PART 1
  3. 1.3.ADD; SUBTRACT; MULTIPLY OR DIVIDE COMPLEX NUMBERS PART 2
  4. 1.4.ARGAND DIAGRAMS
  5. 1.5.THE ARGUMENT OF A COMPLEX NUMBER
  6. 1.6.THE POLAR FORM OF COMPLEX NUMBERS
  7. 1.7.SOLVE EQUATIONS WITH COMPLEX NUMBERS AND TWO VARIABLES
  8. 1.8.COMPLEX NUMBERS COMBINED EXCERCISES

POLYNOMIALS

  1. 2.1.FACTOR AND REMAINDER THEOREM
  2. 2.2.FACTORISE THIRD DEGREE POLYNOMIALS; LONG DIVISION
  3. 2.3.FACTORISE THIRD DEGREE POLYNOMIALS; SYNTHETIC DIVISION
  4. 2.4.FACTORISE THIRD DEGREE POLYNOMIALS; COMBINED EXERCISES

DIFFERENTIAL CALCULUS

  1. 3.1.THE CONCEPT OF A LIMIT
  2. 3.2.THE AVERAGE GRADIENT
  3. 3.3.DIFFERENTIATION FROM FIRST PRINCIPLES
  4. 3.4.DIFFERENTIATION WITH THE POWER RULE
  5. 3.5.EQUATION OF A TANGENT
  6. 3.6.THE CUBIC POLYNOMIAL GRAPH
  7. 3.7.SKETCH A CUBIC POLYNOMIAL GRAPH
  8. 3.8.DETERMINE THE EQUATION OF A CUBIC FUNCTION
  9. 3.9.APPLICATIONS OF DIFFERENTIATION
  10. 3.10.PRACTICAL APPLICATIONS PART 2

INTEGRATION

  1. 4.1.THE CONCEPT OF INTEGRATION
  2. 4.2.STANDARD FORM OF INTEGRALS
  3. 4.3.INTEGRATE POLYNOMIALS
  4. 4.4.DETERMINE THE AREA NCLUDED BY THE CURVE AND X AXIS
  5. 4.5.INDEFINITE INTEGRALS OF EXPONENTIAL FUNCTIONS

ANALYTICAL GEOMETRY

  1. 5.1.EQUATION OF A CIRCLE
  2. 5.2.EQUATION OF A TANGENT TO A CIRCLE
  3. 5.3.POINTS OF INTERSECTION
  4. 5.4.THE ELLIPSE

EUCLIDEAN GEOMETRY

  1. 6.1.THEOREM OF PYTHAGORAS
  2. 6.2.PARALLEL LINES
  3. 6.3.SIMILAR TRIANGLES
  4. 6.4.CONGRUENT TRIANGLES
  5. 6.5.QUADRILATERALS (PART 1)
  6. 6.6.QUADRILATERALS (PART 2)
  7. 6.7.QUADRILATERALS (PART 3)
  8. 6.8.COMBINED EXCERCISES (PART 1)
  9. 6.9.COMBINED EXCERCISES (PART 2)
  10. 6.10.CIRCLE TERMINOLOGY AND THEOREM 1
  11. 6.11.ANGLE AT CENTRE AND ANGLE IN SEMI CIRCLE
  12. 6.12.CYCLIC QUADRILATERALS
  13. 6.13.TANGENTS

TRIGONOMETRY

  1. 7.1.TRIGONOMETRY RATIOS
  2. 7.2.TRIGONOMETRY RECIPROCALS
  3. 7.3.TRIGONOMETRY DIAGRAMS
  4. 7.4.CALCULATIONS
  5. 7.5.TWO DIMENSIONAL PROBLEMS WITH RIGHT ANGLED TRIANGLES
  6. 7.6.TRIGONOMETRY GRAPHS
  7. 7.7.TRIGONOMETRY GRAPHS; VERTICAL MOVEMENT
  8. 7.8.CHANGING PERIODS AND AMPLITUDE
  9. 7.9.TRIG GRAPHS; HORIZONTAL SHIFTS
  10. 7.10.SPECIAL ANGLES
  11. 7.11.REDUCTION FORMULAE
  12. 7.12.TRIG IDENTITIES
  13. 7.13.SINE, COSINE AND AREA RULE
  14. 7.14.TRIG EQUATIONS
  15. 7.15.SOLVING 2D TRIGONOMETRY PROBLEMS
  16. 7.16.SOLVING 2D & 3D TRIGONOMETRY PROBLEMS (PART 1)
  17. 7.17.SOLVING 2D & 3D TRIGONOMETRY PROBLEMS (PART 2)

CIRCLES ANGLES AND ANGULAR MOTION

  1. 8.1.DEFINITION OF A RADIAN
  2. 8.2.CALCULATIONS WITH DEGREES AND RADIANS

FINANCE AND GROWTH

  1. 9.1.SIMPLE AND COMPOUND GROWTH RATE (PART 1)
  2. 9.2.SIMPLE AND COMPOUND GROWTH RATE (PART 2)
  3. 9.3.DEPRECIATION
  4. 9.4.NOMINAL AND EFFECTIVE INTEREST RATE
  5. 9.5.SIMPLE AND COMPOUND FORMULAE; TIMELINES
  6. 9.6.ANNUINITY (PART 1)
  7. 9.7.ANNUINITY (PART 2)
  8. 9.8.ANNUINITY (PART 3)
  9. 9.9.SINKING FUND
  10. 9.10.HIRE PURCHASE AGREEMENT
  11. 9.11.EXCHANGE RATES

REVISION

  1. 10.1.PAPER 1 QUESTION 1
  2. 10.2.PAPER 1 QUESTION 2&3
  3. 10.3.PAPER 1 QUESTION 4
  4. 10.4.PAPER 1 QUESTION 5&6
  5. 10.5.PAPER 1 QUESTION 7
  6. 10.6.PAPER 1 QUESTION 8&9

Questions about access

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