Exponential

Main definitions

This file contains the following definitions: • π, arcsin, arccos, arctan • argument of a complex number • logarithm on real and complex numbers • complex and real power function

Main statements

The following functions are shown to be continuous: • complex and real exponential function • sin, cos, tan, sinh, cosh • logarithm on real numbers • real power function • square root function

Tags

exp, log, sin, cos, tan, arcsin, arccos, arctan, angle, argument, power, square root,


real.continuous_log

Three forms of the continuity of real.log is provided. For the other two forms, see real.continuous_log' and real.continuous_at_log

real.angle

The type of angles

real.arcsin

Inverse of the sin function, returns values in the range -π / 2 arcsin x and arcsin x π / 2. If the argument is not between -1 and 1 it defaults to 0

real.arccos

Inverse of the cos function, returns values in the range 0 arccos x and arccos x π. If the argument is not between -1 and 1 it defaults to π / 2

real.arctan

Inverse of the tan function, returns values in the range -π / 2 < arctan x and arctan x < π / 2

complex.arg

arg returns values in the range (-π, π], such that for x 0, sin (arg x) = x.im / x.abs and cos (arg x) = x.re / x.abs, arg 0 defaults to 0

complex.log

Inverse of the exp function. Returns values such that (log x).im > - π and (log x).im π. log 0 = 0

real.continuous_rpow

real.rpow is continuous at all points except for the lower half of the y-axis. In other words, the function λp:ℝ×ℝ, p.1^p.2 is continuous at (x, y) if x 0 or y > 0.

Multiple forms of the claim is provided in the current section.