Search results
Results From The WOW.Com Content Network
For solving the cubic equation x 3 + m 2 x = n where n > 0, Omar Khayyám constructed the parabola y = x 2 /m, the circle that has as a diameter the line segment [0, n/m 2] on the positive x-axis, and a vertical line through the point where the circle and the parabola intersect above the x-axis.
For example, finding a substitution = + + for a cubic equation of degree =, = + + + such that substituting = yields a new equation ′ = + ′ + ′ + ′ such that ′ =, ′ =, or both. More generally, it may be defined conveniently by means of field theory , as the transformation on minimal polynomials implied by a different choice of ...
If b 2 – 3ac = 0, then there is only one critical point, which is an inflection point. If b 2 – 3ac < 0, then there are no (real) critical points. In the two latter cases, that is, if b 2 – 3ac is nonpositive, the cubic function is strictly monotonic. See the figure for an example of the case Δ 0 > 0.
For example, if the base field F is the field R of real numbers, then x 2 + y 2 = −1 defines an algebraic extension field of R(x), but the corresponding curve considered as a subset of R 2 has no points. The equation x 2 + y 2 = −1 does define an irreducible algebraic curve over R in the scheme sense (an integral, separated one-dimensional ...
As every field extension has degree 2 or 1, and as the field extension over of the coordinates of the original pair of points is clearly of degree 1, it follows from the tower rule that the degree of the field extension over of any coordinate of a constructed point is a power of 2. Now, p(x) = x 3 − 2 = 0 is easily seen to be irreducible over ...
Singular cubic y 2 = x 2 ⋅ (x + 1). A parametrization is given by t ↦ (t 2 – 1, t ⋅ (t 2 – 1)). A cubic curve may have a singular point, in which case it has a parametrization in terms of a projective line. Otherwise a non-singular cubic curve is known to have nine points of inflection, over an algebraically closed field such as the ...
Recover deleted files, songs, photos, videos, stored digital media device files and more. Download your free 30 day trial from AOL today.
The resolvent cubic R 3 (y) has a root of the form α 2, for some non-null rational number α (again, this can be determined using the rational root theorem). The number a 2 2 − 4a 0 is the square of a rational number and a 1 = 0. Indeed: