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numbers and algebraic expressions
logic, sets, intervals
absolute value
function and its properties
linear function
quadratic function
polynomials
rational function
exponential function
logarithm
number sequences
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derivative and integral of functions
trigonometry
plane geometry
analytic geometry
solid geometry
combinatorics
probability
elements of statistics
kropki game

Union: A ∪ B. The Union of sets A and B is the set of all elements which are in A, in B, or in both A and B. Example: A = {1, 3}, B = {3, 5}, A ∪ B = {1, 3, 5}. Intersection: A ∩ B. The Intersection of sets A and B is the set of all elements which are in both A and B. Example: A = {1, 3}, B = {3, 5}, A ∩ B = {3}. Difference: A ∖ B. The Difference of sets A and B is the set of all elements which are in A but not in B. Example: A = {1, 3, 8}, B = {3, 5}, A ∖ B = {1, 8}. Complement: A'. The Complement of set A to the set X is the set of all elements which are in X but not in A. Example: X = {1, 4, 6, 7}, A = {1, 7}, A' = {4, 6}.