ответ: n = 9 .
Объяснение:
(a ₙ) : a₁ = 5; d = 3 ; a ₙ= 29 ; n - ?
a ₙ = a₁ + d (n - 1 );
29 = 5 + 3 (n - 1 ) ;
3( n - 1 ) = 24 ;
n - 1 = 24 /3 ;
n - 1 = 8 ;
n = 9 .
1) x^2 -34+3x^2=10
y=3-3x =>4x^2-3x-10=0
x1=3+13/8=2 y1=3-6=-3
x2=3-13/8=5/4 y2=12/4-15/4=-3/4
2)x^2-y^2=64 => 25y^2/9 -y^2=64 => 25y^2-9y^2=576
3x=-5y => x=-5y/3 16y^2=576
y^2=36
y= 6, y = -6
x=-30/3=-10 x=30/3=10
ответ: n = 9 .
Объяснение:
(a ₙ) : a₁ = 5; d = 3 ; a ₙ= 29 ; n - ?
a ₙ = a₁ + d (n - 1 );
29 = 5 + 3 (n - 1 ) ;
3( n - 1 ) = 24 ;
n - 1 = 24 /3 ;
n - 1 = 8 ;
n = 9 .