РОЗДІЛ 2. Раціональні вирази - Вправи 50 - 200 » 148 (6-8)

6) (-5+ c^2)/(c-2) – 1/(2-c) = 〖-5+c〗^2/(c-2) + 1/(c-2) = (〖-5+c〗^2+ 1)/(c-2) = (c^2- 4)/(c-2) = ((c-2)(c+2))/(c-2) = c + 2; 7) n^2/(3n-33) + 121/(33-3n) = n^2/(3n-33) – 121/(3n-33) = (n^2- 121)/(3n-33) = ((n-11)(n+11))/(3(n-11)) = (n+11)/3; 8) (y^2- 4y)/(y^2- 4y+4) – 2y/(4y- y^2- 4) = (y^2- 4y)/〖(y-2)〗^2 + 2y/(y^2- 4y+4) = (y^2- 4y)/〖(y-2)〗^2 + 2y/〖(y-2)〗^2 = (y^2- 4y+2y)/〖(y-2)〗^2 = (y^2- 2y)/〖(y-2)〗^2 = (y(y-2))/〖(y-2)〗^2 = y/(y-2).