РОЗДІЛ 2. Раціональні вирази - Вправи 50 - 200 » 164 (4-6)

4) (1-t)/(t^2- t) – (t+1)/〖1-t〗^2 = (1-t)/(t(t-1)) – (t+1)/((1-t)(1+t)) = –(t-1)/(t(t-1)) + (t+1)/((t-1)(t+1)) = –1^(\t-1)/t + 1^(\t)/(t-1) = (-t+1+t)/(t(t-1)) = 1/(t(t-1)); 5) a^2/〖(a-3)〗^2 + a/(3-a) = a^2/〖(3-a)〗^2 + a^(\3-a)/(3-a) = (a^2+ 3a- a^2)/〖(3-a)〗^2 = 3a/〖(3-a)〗^2 ; 6) (b+1)/〖(b-1)〗^2 + 2/〖1-b〗^2 – 1/(b+1) = 〖b+1〗^(\1+b)/〖(1-b)〗^2 + 2^(\1-b)/((1-b)(1+b)) – 1^(\(〖1-b)〗^2 )/(1+b) = (〖(1+b)〗^2+ 2-2b-(1-2b+ b^2))/((1-b)^2 (1+b)) = (2b+2)/((1-b)^2 (1+b)) = (2(b+1))/((1-b)^2 (1+b)) = 2/〖(1-b)〗^2 .