-1≤ sint≤1
1/(√7-√3) = (√7+√3)/[(√7-√3)(√7+√3) = (√7+√3)/4 >1 ⇒ t = ∅
18^n+3/3^2n+5=18^n+3/6^3n+3=3^4n
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1. х^2-6x+9
2. 4a^2+20aв+25в^2
3. a^2-4
4. 9x^2-y^2
5. x^3+4x^2+16x-4x^2-16x-64=x^3-64
Q=(x+2)/(3x-2)=(x+8)/(x+2)
x≠2/3 x≠-2
(x+2)²=(3x+2)(x+8)
3x²+24x+2x+16-x²-4x-4=0
2x²+22x+12=0
x²+11x+6=0
D=121-24=97
x1=(-11-√97)/2 U x2=(-11+√97)/2
b1=3x-2=(-33-3√97-4)/2=(-37-√97)/2 U b1=(-33+√97)/2
b2=(-11-√97+4)/2=(-7-√97)/2 U b2=(-7+√97)/2
b3=(-11-√97+16)/2=(5-√97)/2 U b3=(5+√97)/2