Неравенство 1/(x+1)+1/(3-x)<=1

Question

Неравенство
1/(x+1)+1/(3-x)<=1

Answer 1

1/(x+1)+1/(3-x)≤1   ОДЗ: x+1≠0   x≠-1     3-x≠0     x≠3
(3-x+x+1)/((x+1)*(3-x))≤1
4≤-x²+2x+3
x²-2x+1≤0
(x-1)²≤0
x=1
Ответ: x=1.