x^2 -6x +24 - 4x +1 = 0
<span> x^2+1/ x+1 * x^2+2x+1/ 1-x^4 = (x^2 + 1)(x+1)^2 / (x+1)(1-x^2)(1+x^2) = (x+1)/(1-x)(1+x) = 1/(1-x) </span>
минус котангенс альфа .............................. ...... . . ....