I. Pinelis

math.CA2020

A problem concerning Riemann sums

Iosif Pinelis

An open problem concerning Riemann sums, posed by O. Furdui, is considered.

math.CA2020

Exact lower and upper bounds on the incomplete gamma function

Iosif Pinelis

Lower and upper bounds $B_{a} (x)$ on the incomplete gamma function $Γ (a, x)$ are given for all real $a$ and all real $x > 0$ . These bounds $B_{a} (x)$ are exact in the sense that $B_a(x)\u…

math.CA2020

Identities and inequalities for the cosine and sine functions

Iosif Pinelis

Identities and inequalities for the cosine and sine functions are obtained.