Definite integrals and sums involving the floor function are quite common in problems and applications.
Floor function limit proof.
The best strategy is to break up the interval of integration or summation into pieces on which the floor function is constant.
Formal definition of a function limit.
For y fixed and x a multiple of y the fourier series given converges to y 2 rather than to x mod y 0.
The value of a.
And this is the ceiling function.
Floor and ceiling functions.
The int function short for integer is like the floor function but some calculators and computer programs show different results when given negative numbers.
Int limits 0 infty lfloor x rfloor e x dx.
So the function increases without bound on the right side and decreases without bound on the left side.
At points of continuity the series converges to the true.
We can take δ 1 n delta frac1n δ n 1 and the proof of the second statement is similar.
Ceiling and floor functions.
Evaluate 0 x e x d x.
At points of discontinuity a fourier series converges to a value that is the average of its limits on the left and the right unlike the floor ceiling and fractional part functions.
Sgn x sgn x floor functions.
0 x.
The graphs of these functions are shown below.