Odpowiedź:
[tex]a)\ \ -2x^3(6x+2)(4x^3-x^2)=(-12x^4-4x^3)(4x^3-x^2)=\\\\=-48x^7+12x^6-16x^6+4x^5=-48x^7-4x^6+4x^5\\\\\\b)\ \ (x+3y^2)(5x^4y^2-15x^3y^4)=5x^5y^2-15x^4y^4+15x^4y^4-45x^3y^6=\\\\=5x^5y^2-45x^3y^6[/tex]
[tex]c)\ \ (a^4+3a-2)^2=(a^4)^2+(3a)^2+(-2)^2+2a^4\cdot3a+2a^4\cdot(-2)+2\cdot3a\cdot(-2)=\\\\=a^8+9a^2+4+6a^5-4a^4-12a=a^8+6a^5-4a^4+9a^2-12a+4[/tex]
[tex]Zastosowany\ \ wz\'or\\\\(a+b+c)^2=a^2+b^2+c^2+2ab+2ac+2bc[/tex]
