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Simple calculator

x :
y :
z :





High School

Addition, subtraction, multiplication, (modulus) division (x o yz).

Decimal converted to hexadecimal, ... (xz).
Hexadecimal, ... converted to decimal (xz).

Examples:
43 div 16 = 2.6875 = 43 + 11/16, 43 mod 16 = 11.

2b hex = 2×16 + 11 = 43 dec,
43 dec = 2 (quotient) + 11 (modulus), i.e. 2b hex,
4b hex = 0100 1011 bin.

Teachers

Sqrt(x) = "square root of x",
Pov(x,y) = xy, Exp(x) = ex, Ln(x) = logex,
Log(x,y) = logyx.
Sin, cos, tan of x in radian.

e = 2.718281828459045... , π = 3.1415926535897932...,
x rad = x⋅180/π deg, and vice versa x deg = xπ/180 rad.

Examples: 30° = 30°⋅π/180° ≈ 0.5236

sin 0.5236 = 0.5 <=> asin 0.5 = 0.5236 (rad).

Gimnazija Hall

Trigonometric functions of a right triangle:
Sine: sin x = Opposite / Hypotenuse,
Cosine: cos x = Adjacent / Hypotenuse,
Tangent: tan x = Opposite / Adjacent.

Basic trigonometric identities:
cos2 x + sin2x = 1, tan x = sin x/cos x, cot x = 1/tan x,
cos2 x - sin2x = cos 2x, 2 sin x cos x = sin 2x.

Secant and cosecant functions:
sec x = 1/cos x, csc x = 1/sin x,
tan2 x + 1 = sec2 x, cot2 x + 1 = csc2 x.

Entrance to Gimnazija

Hyperbolic functions are derived:
cosh x = (exp(x) + exp(-x))/2, sinh x = (exp(x) - exp(-x))/2,
i.e. hyperbolic cosine and sine:
cosh - pronounce: "kosh", sinh - rhymes with the "Grinch".

Basic hiperbolic identities:
cosh2 x - sinh2 x = 1,
tanh x = sinh x/coth x,
coth x = 1/tanh x.