1) (х² + 1)/( х - 4) - (х² -1)/(х + 3) = 23/1 |·(x - 4)(x + 3) ≠0
x ≠ 4, x ≠-3
(x²+1)(x + 3) -(x² -1)(x - 4) = 23(x + 3)( x - 4)
х³ + 3х² + х + 3 - х³ + 4х² + х - 4 = 23(х² - х -12)
7х² + 2х -1 = 23х² -23х - 276
16х² - 25х - 275 = 0
D = 18225 = 135²
х1 = (25 + 135)/32 = 160/32= 5
х2 = ( 25 - 135)/32 = -110/32 = -55/16
2) 2/(3 - х) + 1/2 = 6/х(3 - х) |· 2x(3 - x) ≠0
x ≠0, x ≠3
4x + 3x - x³ = 12
x² - 7x +12 = 0
По т. Виета х1 = 4, х2 = 3(посторонний корень)
Ответ: 4