a) $$15(a^2 - b^2) = 15(a-b)(a+b)$$
б) $$29(a^2 + b^2 + 2ab) = 29(a+b)^2$$
в) $$10(a^3 + b^3) = 10(a+b)(a^2 - ab + b^2)$$
г) $$18(a^3 - b^3) = 18(a-b)(a^2 + ab + b^2)$$
д) $$47(a^6 - b^6) = 47(a^3 - b^3)(a^3 + b^3) = 47(a-b)(a^2+ab+b^2)(a+b)(a^2-ab+b^2)$$
е) $$51(a^6 + b^6) = 51(a^2+b^2)(a^4-a^2b^2+b^4)$$