Polynomial of degree 5: f(x) = (x+4)(x+2)(x+1)(x-1)(x-3)/20+2
Quintic functions are polynomial functions in which the highest degree is five. Because they have an odd degree, normal quintic functions appear similar to normal cubic functions when graphed, except for the fact that they may possess an additional local maximum and minimum each. The derivative of a quintic function is a quartic function.
The derivative of a quinticfunction is a quartic function.
A quintic is solvable using radicals if the Galois group of the quintic (which is a subgroup of the symmetric group S(5) of permutations of a five element set) is a solvable group.
Attempting to apply it to a quintic, we seek for the equation of which the root is (a+wb+w2c+wad+w4e), w an imaginary fifth root of unity, or rather the fifth power thereof (a+wb+w2c+wad+w4e)6; this is a 24-valued function, but if we consider the four values corresponding to the roots of unity w, w2, co3, w4, viz.
Finally, Ruffini (1799) and Abel (1826) showed that the solution of the general quintic cannot be written as a finite formula involving only the four arithmetic operations and the extraction of roots.
be a branch of the inverse function of
Galois groups of quintics are related to the symmetries of the icosahedron.