mathinschool.com
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
limits of sequences and functions
derivative and integral of functions
trigonometry
plane geometry
analytic geometry
solid geometry
combinatorics
probability
elements of statistics
kropki game

Instead memorize values of sin, cos, tan and cot for 45° can them calculate. Draw the isosceles right triangle. Its angles equal 90°, 45°, 45°. Let triangle have legs of length 1. Length of hypotenuse calculate from Pythagorean theorem. Instead memorize values of sin, cos, tan and cot for 30° and 60° can them calculate. Draw the equilateral triangle and split by height into two right triangle. Angles of this right triangle equal 90°, 60°, 30°. Let length of side of the equilateral triangle equals 2. Lenght of height calculate from Pythagorean theorem.