<prompt> Acha r_1, r_2,r_3, na r_4 ziwe mizizi yax4 - 2x3 - 5x2 4x - 1 0.Tafuta monic polynomial, katika x, ambayo mizizi yake ni frac1r_1, frac 1r_2, frac1r_3, na frac1r_4.  <response>: Acha x frac1y, hivyofrac1y4 - frac2y3 - frac5y2 frac4y - 1 0. Ili kubadilisha hii kuwa monic polynomial, tunazidisha kwa -y4, ambayo inatupa y4 - 4y3 5y2 2y - 1 0. Polynomial sambamba katika x ni basi. x4 - 4x3 5x2 2x - 1 0. 