Question

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Answer 1

   
[tex]Ex.~9) \\ a)~(a+2)(a^2-2a+4) = a^3-2a^2+4a + 2a^2-4a+8 = a^3 + 8 \\ b)~(x-1)(x^2+x+1)=x^3+x^2+x - x^2-x-1=x^3-1 \\ c)~(x+5)(x^2-5x+25)= \\ =x^3-5x^2+25x + 5x^2-25x+125= x^3+125 \\ d)~(y-3)(y^2+3y+9)=y^3-27 \\ e) ~ (x^2+y^2)(x^4-x^2y^3+y^6) = x^6 +y^8 \\ f)~(x-2n)(x^2+2xn+4n^2)=x^3-8n^3 [/tex]