Question

Найдите А , если 1/3+1/4+1/а=1

Answer 1

1/a = 1 - 1/3 - 1/4
1/a = 2/3 - 1/4
1/a = 8/12 - 3/12
1/a = 5/12
5/5a = 5/12
5a = 12
a = 12/5

Answer 2

1/4+1/3+1/а=1, 1/4+1/3+1/а-1=0, при а не равно 0, 3а+4а+12-12а=0, 5а=12, а=12/5, а=2,4