Вправи 1001 - 1100 » 1095

1095. Знайди суму і різницю дробів: б) 1/(〖6a〗^2-13a+6) + 1/(〖3a〗^2- 11a+6) = 1/(6(a-1,5)(a- 2/3)) + 1/(3(a-3)(a- 2/3)) = (a-3+2(a-1,5))/(6(a-1,5)(a- 2/3)(a-3)) = (a-3+2a-3)/(6(a-1,5)(a- 2/3)(a-3)) = (3a-6)/((2a-3)(3a-2)(a-3)) = (3(a-2))/(2a-3)(3a-2)(a-3) ; 1/(〖6a〗^2- 13a+6) – 1/(3a^2- 11a+6) = 1/((2a-3)(3a-2)) – 1/((a-3)(3a-2)) = (a-3-2a+3)/((2a-3)(3a-2)(a-3)) = a/((2a-3)(3a-2)(a-3)). a = (13 ± √(169-144))/12 = (13 ±5)/12; a1 = 18/12 = 1,5; a2 = 8/12 = 2/3; a’ = (11 ± √(121-72))/12 = (11 ±7)/12; a_1^' = 18/6 = 3; a_2^' = 4/6 = 2/3;