Вправи 101 - 200 » 138

138. Спростіть вираз: 1) (a-b)/3b • 3/(a-b) = ((a-b) • 3)/(3b(a-b)) = 1/b; 2) (2mn+ n^2)/6m • 2m/n = (nm(2m+n) • 2m)/(6m • n) = (2m+n)/3; 3) (7a+7b)/b^6 • b^3/(a+b) = (7(a+b) • b^3)/(b^6 • (a+b)) = 7/b^3 ; 4) (32a • (a-3))/((a-3)(a+3) • 8a) = 1/(a+3); 5) (c-1)/(c+6) • (c+6)/(c^2- 2c+1) = ((c-1)(c+6))/((c+6)(c-1)^2 ) = 1/(c-1); 6) (m-2)/(m^2- 49) • (m+7)/(m-2) = ((m-2)(m+7))/((m-7)(m+7)(m-2)) = 1/(m-7); 7) (a+4)/1 • a/(2a+8) = ((a+4) • a)/(1 • 2(a+4) ) = a/2; 8) (x-9)/(4x+8) • (x^2+ 2x)/(x-9) = ((x-9) • x(x+2))/(4(x+2)•(x-9)) = x/4; 9) (4a^2- 4a+1)/(3a+3) • (a+1)/(2a-1) = ((2a-1)^2 • (a+1))/(3(a+1)•(2a-1)) = (2a-1)/3; 10) (a^2- 25)/4a • (4a^2)/(a^2-5a) = (〖(a〗^2- 25)a)/(a^2-5a) = ((a-5)(a+ 5)a)/(a(a-5)) = a + 5.