In this paper, we prove the generalized Hyers--Ulamstability of a quadratic and quartic functional equation inintuitionistic fuzzy Banach spaces.

alkanolamine solutions such as 2-amino-2-methyl-1-propanol (amp) are widely used in chemical industries for the removal of acid gases such as co2 and h2s. in this work, the density of co2, amp, water, and amp solutions using the goharshadi–morsali–abbaspour equation of state “gma eos” in the extended 50-degree range of temperatures (313.06-362.65 k) and pressures (0.5-40 mpa) was calculated. th...

solubility of high molecular weight n-paraffins in supercritical carbon dioxide has been a matter of interest to many researchers. however, not sufficient solubility experimental data are available although the methods by which the experimental data are obtained have many varieties. utilizing cubic equations of state is an effective method for solubility prediction of n-paraffins in supercritic...

In this paper, we solve the quadratic $alpha$-functional equations $2f(x) + 2f(y) = f(x + y) + alpha^{-2}f(alpha(x-y)); (0.1)$ where $alpha$ is a fixed non-Archimedean number with $alpha^{-2}neq 3$. Using the fixed point method and the direct method, we prove the Hyers-Ulam stability of the quadratic $alpha$-functional equation (0.1) in non-Archimedean Banach spaces.

the study of stability problems of functional equations was motivated by a question of s.m. ulam asked in 1940. the first result giving answer to this question is due to d.h. hyers. subsequently, his result was extended and generalized in several ways.we prove some hyperstability results for the equation g(ax+by)+g(cx+dy)=ag(x)+bg(y)on restricted domain. namely, we show, under some weak natural...

Let Sr be the blow-up of P 2 in r general points, i.e., a smooth Del Pezzo surface of degree 9 − r. For r ≤ 7, we determine the quadratic equations defining its Cox ring explicitly. The ideal of the relations in Cox(S8) is calculated up to radical. As conjectured by Batyrev and Popov, all the generating relations are quadratic.

The type II1 unprojection is, by definition, the generic complete intersection type II unprojection, in the sense of [P] Section 3.1, for the parameter value k = 1, and depends on a parameter n ≥ 2. Our main results are the explicit calculation of the linear relations of the type II1 unprojection for any value n ≥ 2 (Theorem 3.16) and the explicit calculation of the quadratic equation for the c...