<span>(X+5)</span>²<span>-(x-3)</span>²<span> = 0
x</span>²+10x+25-(x²-6x+9)=0
x²+10x+25-x²+6x-9=0
16x+16=0
16x=-16
x=16:-16
x=-1
Ответ: -1
2с(a+1)+b(a+1)=(a+1)(2c+b)
4x²-20x=0
4x(x-5)=0
4x=0 x-5=0
x1=0 x2=5
Ответ:
b₁=81; n=6
Объяснение:
Sₙ=(b₁-bₙ·q)/(1-q)
182/3=(b₁-(-1/3)·(-1/3))/(1-(-1/3))
182/3=(b₁ -1/9)/(4/3)
182/3=(b₁ -1/9)·3/4
4·182=9·(b₁ -1/9)
728=9b₁ -9/9
9b₁=728+1
b₁=729/9=81
bₙ=b₁·qⁿ⁻¹
-1/3=81·(-1/3)ⁿ⁻¹
(-1/3)ⁿ⁻¹=(-1/3)/9²
(-1/3)ⁿ⁻¹=(-1/3)/(3²)²
(-1/3)ⁿ⁻¹=(-1/(3·3⁴)
(-1/3)ⁿ⁻¹=(-1/3)⁵
n-1=5
n=5+1=6