1
x²-2x+1=2x²-2x+1
x²=0
x=0
2
x²+3^x+5>x²+9^x-3^x
9^x-2*3^x<0
3^X*(3^x-2)<0
3^x=0 3^x=2
0<3^x<2
x∈(-∞;log(3)2)
3
x²+2<3x
x²-3x+2<0
x1+x2=3 U x1*x2=2
x1=1 U x2=2
x∈(1;2)
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S6=a1(q^5-1)/q-1 =18(1.5^5-1)/0.5 scitaem i poluchaem otvet
<span>7 tg x – 10ctg x + 9 = 0 | * tgx
7 tg</span>²<span>x -10 +9tgx = 0
tgx = z
7z</span>² + 9z -10 = 0
z₁ = -2 z₂ = 5/7
tgx = -2 tgx = 5/7
x = arctg(-2) + πk , k ∈Z x = arctg(5/7 ) + πn , n ∈Z