A1=-8
a2=-1
d=a2-a1=-8-(-1)=-7
an=<span>a1 + d ( n – 1 )
a7=-8+-7(7-1)=-34
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5m^4 - 320mn^3 =
= 5m (m^3 - 64n^3) =
= 5m (m - 4n)(m^2 + 4mn + 16n^2)
<span>1)
Дано: Решение: b2=0.5*(-128) = -64
b1=-128 b3=0.5*(-64) = -32
bn+1=1/2bn b4=0.5*(-32)=-16
Найти: b5=0.5*(-16)=-8
b5
Ответ: b5=-2</span>
<span>4/9a^2+4ab+9b^2 = (2/3 a + 3b)</span>²