is there any calculator in software centre which could solve quadratic equations?

I want good scientific calculator which can calculate the roots of any quadratic equation just by entering the quadratic equation

first of all is any app like those there in ubuntu software centre??

2 Answers

It's very simple in octave, just by entering the coefficients of the equation into the roots function

octave:1> roots([1,0,-1])
ans = -1 1

See the online help

octave:2> help roots 'roots' is a function from the file /usr/share/octave/3.8.1/m/polynomial/roots.m -- Function File: roots (V) For a vector V with N components, return the roots of the polynomial v(1) * z^(N-1) + ... + v(N-1) * z + v(N) As an example, the following code finds the roots of the quadratic polynomial p(x) = x^2 - 5. c = [1, 0, -5]; roots (c) => 2.2361 => -2.2361 Note that the true result is +/- sqrt(5) which is roughly +/- 2.2361. See also: poly, compan, fzero.

Qalculate! might fit your needs: