2x+y=13
y=7+x
2x+7+x=13
3x=13-7
3x=6
x=2
y=9
ОТВЕТ:2; 9.
Пошаговое объяснение:
(n+2)!((n+3)(n+4)-1)
lim --------------------------- = 'сократим (n+2)! '
x->∞ (n+2)!(n+3)
(n+3)(n+4)-1
=lim --------------------------- =
x->∞ (n+3)
n²+7n+12-1
=lim -------------------- =
x->∞ (n+3)
n²+7n+11
=lim -------------------- =
x->∞ (n+3)
n( n+7+1/n)
=lim -------------------- = ' сократим на n ; 1/n, 3/n ->0
x->∞ n(1+3/n)
n+7
=lim -------------------- = ∞
x->∞ 1
б)
х=2
у=9
2+2+9=13
9-2=7