1) (b+3)(b2-b-7)=b3-b2-7b+3b2-3b-27=b3+2b2-10b-27 2) (a+4)(a2+a-2)=a3+a2-2a+4a2+4a-8=a3+5a2+2a-8 3) (3xy-4)(6+xy)=18xy-3x2y2-24-4xy=14xy-3x2y2-24
Чо такоэ cos и sin!? яб могла помогти без сос и зин!
27x^3-y^3+9x^2*y-3xy^2=(3x-y)(9x^2 +3xy+y^2)+3xy(3x-y)
3p(8c+1)-8c(3p-5) = 24cp+3p-24cp+40c= <span>3p+40c
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</span><span>5n^2(3n+1)-2n(5n^2-3)= 15n^3+5n^2-10n^3+6n= 5n^3+5n^2+6n</span>