Вправи 301 - 400 » 393

393. Спростіть вираз: 1) 1/x + x–1 = 1/x + 1/x = (1+1)/x = 2/x; 2) 2/a + a–1 = 2/a + 1/a = (2+1)/a = 3/a; 3) 3/m^2 + m–2 = 3/m^2 + 1/m^2 = (3+1)/m^2 = 4/m^2 ; 4) (x + 5)–1 + 1/(x+5) = 1/(x+5) + 1/(x+5) = 2/(x+5); 5) (a + 2)–1 – 2/(a+2) = 1/(a+2) – 2/(a+2) = –1/(a+2); 6) a(a + b)–1 + b(a + b)–1 = a/(a+ b) + b/(a+ b) = (a+ b)/(a+ b) = 1; 7) (1 + b)0 – (1 + b)–1 = 1^(\1+b) – 1/(1+ b) = (1+ b-1)/(1+ b) = b/(1+ b); 8) (a + b)–1 + (a + b)0 = 1/(a+ b) + 1^(\a+b) = (1+ a+ b)/(a+ b); 9) (x – 2)–1 – x(2 – x)–1 = 1/(x-2) – x/(2- x) = 1/(x-2) + x/(x-2) = (1+ x)/(x-2); 10) (5 – b)–1 + (5 – b)–1 = 1^(\5-b)/(5+ b) + 1^(\5+b)/(5-b) = (5- b+5+ b)/((5+ b)(5- b)) = 10/〖25- b〗^2 .