q=∛(b4/b1)=∛(6/20582)=∛1/343=1/7
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1)(a+b)(a-b)(a²+b²)=(a²-b²)(a²+b²)=aˇ4 - bˇ4
2)c(c-2)(c+2)-(c-1)(c²+c+1)=c(c²-4)-(c³-1)=c³-4c-c³+1=-4c+1
3)2x+2y-x²-2xy-y²=2(x+y)-(x²+2xy+y²)=2(x+y)-(x+y)(x+y)=
=(x+y)(2-x-y)
F(5)- x=5, 5>0; f(5)=5^2=25; Ответ:25