Solve a^{5}b^{7}(a+b)^9+4a^6b^0(a+b)^7

$$a ^ { 5 } b ^ { 7 } ( a + b ) ^ { 9 } + 4 a ^ { 6 } b ^ { 0 } ( a + b ) ^ { 7 }$$

Factor

$$a^{5}\left(a+b\right)^{7}\left(a^{2}b^{7}+2ab^{8}+4a+b^{9}\right)$$

Solution Steps

Factor out common term a^{5} by using distributive property.

$$a^{5}\left(b^{7}\left(a+b\right)^{9}+4b^{7}a+28b^{6}a^{2}+84b^{5}a^{3}+140b^{4}a^{4}+140b^{3}a^{5}+84b^{2}a^{6}+28ba^{7}+4a^{8}\right)$$

Consider b^{7}\left(a+b\right)^{9}+4b^{7}a+28b^{6}a^{2}+84b^{5}a^{3}+140b^{4}a^{4}+140b^{3}a^{5}+84b^{2}a^{6}+28ba^{7}+4a^{8}. Simplify.

$$9a^{8}b^{8}+4a^{8}+36a^{7}b^{9}+84a^{6}b^{10}+126a^{5}b^{11}+126a^{4}b^{12}+140a^{4}b^{4}+84a^{3}b^{13}+84a^{3}b^{5}+36a^{2}b^{14}+28a^{2}b^{6}+9ab^{15}+4ab^{7}+b^{16}+b^{7}a^{9}+140b^{3}a^{5}+84b^{2}a^{6}+28ba^{7}$$

Consider 9a^{8}b^{8}+4a^{8}+36a^{7}b^{9}+84a^{6}b^{10}+126a^{5}b^{11}+126a^{4}b^{12}+140a^{4}b^{4}+84a^{3}b^{13}+84a^{3}b^{5}+36a^{2}b^{14}+28a^{2}b^{6}+9ab^{15}+4ab^{7}+b^{16}+b^{7}a^{9}+140b^{3}a^{5}+84b^{2}a^{6}+28ba^{7} as a polynomial over variable a.

$$b^{7}a^{9}+\left(9b^{8}+4\right)a^{8}+\left(36b^{9}+28b\right)a^{7}+\left(84b^{10}+84b^{2}\right)a^{6}+\left(126b^{11}+140b^{3}\right)a^{5}+\left(126b^{12}+140b^{4}\right)a^{4}+\left(84b^{13}+84b^{5}\right)a^{3}+\left(36b^{14}+28b^{6}\right)a^{2}+\left(9b^{15}+4b^{7}\right)a+b^{16}$$

Find one factor of the form b^{k}a^{m}+n, where b^{k}a^{m} divides the monomial with the highest power b^{7}a^{9} and n divides the constant factor b^{16}. One such factor is a+b. Factor the polynomial by dividing it by this factor.

$$\left(a+b\right)\left(8a^{7}b^{8}+4a^{7}+28a^{6}b^{9}+56a^{5}b^{10}+70a^{4}b^{11}+56a^{3}b^{12}+60a^{3}b^{4}+28a^{2}b^{13}+24a^{2}b^{5}+8ab^{14}+4ab^{6}+b^{15}+b^{7}a^{8}+80b^{3}a^{4}+60b^{2}a^{5}+24ba^{6}\right)$$

Consider 8a^{7}b^{8}+4a^{7}+28a^{6}b^{9}+56a^{5}b^{10}+70a^{4}b^{11}+56a^{3}b^{12}+60a^{3}b^{4}+28a^{2}b^{13}+24a^{2}b^{5}+8ab^{14}+4ab^{6}+b^{15}+b^{7}a^{8}+80b^{3}a^{4}+60b^{2}a^{5}+24ba^{6}. Consider 8a^{7}b^{8}+4a^{7}+28a^{6}b^{9}+56a^{5}b^{10}+70a^{4}b^{11}+56a^{3}b^{12}+60a^{3}b^{4}+28a^{2}b^{13}+24a^{2}b^{5}+8ab^{14}+4ab^{6}+b^{15}+b^{7}a^{8}+80b^{3}a^{4}+60b^{2}a^{5}+24ba^{6} as a polynomial over variable a.

$$b^{7}a^{8}+\left(8b^{8}+4\right)a^{7}+\left(28b^{9}+24b\right)a^{6}+\left(56b^{10}+60b^{2}\right)a^{5}+\left(70b^{11}+80b^{3}\right)a^{4}+\left(56b^{12}+60b^{4}\right)a^{3}+\left(28b^{13}+24b^{5}\right)a^{2}+\left(8b^{14}+4b^{6}\right)a+b^{15}$$

Find one factor of the form b^{p}a^{q}+u, where b^{p}a^{q} divides the monomial with the highest power b^{7}a^{8} and u divides the constant factor b^{15}. One such factor is a+b. Factor the polynomial by dividing it by this factor.

$$\left(a+b\right)\left(a^{7}b^{7}+7a^{6}b^{8}+4a^{6}+21a^{5}b^{9}+35a^{4}b^{10}+35a^{3}b^{11}+40a^{3}b^{3}+21a^{2}b^{12}+20a^{2}b^{4}+7ab^{13}+4ab^{5}+b^{14}+40b^{2}a^{4}+20ba^{5}\right)$$

Consider a^{7}b^{7}+7a^{6}b^{8}+4a^{6}+21a^{5}b^{9}+35a^{4}b^{10}+35a^{3}b^{11}+40a^{3}b^{3}+21a^{2}b^{12}+20a^{2}b^{4}+7ab^{13}+4ab^{5}+b^{14}+40b^{2}a^{4}+20ba^{5}. Consider a^{7}b^{7}+7a^{6}b^{8}+4a^{6}+21a^{5}b^{9}+35a^{4}b^{10}+35a^{3}b^{11}+40a^{3}b^{3}+21a^{2}b^{12}+20a^{2}b^{4}+7ab^{13}+4ab^{5}+b^{14}+40b^{2}a^{4}+20ba^{5} as a polynomial over variable a.

$$b^{7}a^{7}+\left(7b^{8}+4\right)a^{6}+\left(21b^{9}+20b\right)a^{5}+\left(35b^{10}+40b^{2}\right)a^{4}+\left(35b^{11}+40b^{3}\right)a^{3}+\left(21b^{12}+20b^{4}\right)a^{2}+\left(7b^{13}+4b^{5}\right)a+b^{14}$$

Find one factor of the form b^{v}a^{w}+c, where b^{v}a^{w} divides the monomial with the highest power b^{7}a^{7} and c divides the constant factor b^{14}. One such factor is a+b. Factor the polynomial by dividing it by this factor.

$$\left(a+b\right)\left(a^{6}b^{7}+6a^{5}b^{8}+4a^{5}+15a^{4}b^{9}+20a^{3}b^{10}+15a^{2}b^{11}+16a^{2}b^{3}+6ab^{12}+4ab^{4}+b^{13}+24b^{2}a^{3}+16ba^{4}\right)$$

Consider a^{6}b^{7}+6a^{5}b^{8}+4a^{5}+15a^{4}b^{9}+20a^{3}b^{10}+15a^{2}b^{11}+16a^{2}b^{3}+6ab^{12}+4ab^{4}+b^{13}+24b^{2}a^{3}+16ba^{4}. Consider a^{6}b^{7}+6a^{5}b^{8}+4a^{5}+15a^{4}b^{9}+20a^{3}b^{10}+15a^{2}b^{11}+16a^{2}b^{3}+6ab^{12}+4ab^{4}+b^{13}+24b^{2}a^{3}+16ba^{4} as a polynomial over variable a.

$$b^{7}a^{6}+\left(6b^{8}+4\right)a^{5}+\left(15b^{9}+16b\right)a^{4}+\left(20b^{10}+24b^{2}\right)a^{3}+\left(15b^{11}+16b^{3}\right)a^{2}+\left(6b^{12}+4b^{4}\right)a+b^{13}$$

Find one factor of the form b^{d}a^{e}+f, where b^{d}a^{e} divides the monomial with the highest power b^{7}a^{6} and f divides the constant factor b^{13}. One such factor is a+b. Factor the polynomial by dividing it by this factor.

$$\left(a+b\right)\left(a^{5}b^{7}+5a^{4}b^{8}+4a^{4}+10a^{3}b^{9}+10a^{2}b^{10}+12a^{2}b^{2}+5ab^{11}+4ab^{3}+b^{12}+12ba^{3}\right)$$

Consider a^{5}b^{7}+5a^{4}b^{8}+4a^{4}+10a^{3}b^{9}+10a^{2}b^{10}+12a^{2}b^{2}+5ab^{11}+4ab^{3}+b^{12}+12ba^{3}. Consider a^{5}b^{7}+5a^{4}b^{8}+4a^{4}+10a^{3}b^{9}+10a^{2}b^{10}+12a^{2}b^{2}+5ab^{11}+4ab^{3}+b^{12}+12ba^{3} as a polynomial over variable a.

$$b^{7}a^{5}+\left(5b^{8}+4\right)a^{4}+\left(10b^{9}+12b\right)a^{3}+\left(10b^{10}+12b^{2}\right)a^{2}+\left(5b^{11}+4b^{3}\right)a+b^{12}$$

Find one factor of the form b^{g}a^{h}+j, where b^{g}a^{h} divides the monomial with the highest power b^{7}a^{5} and j divides the constant factor b^{12}. One such factor is a+b. Factor the polynomial by dividing it by this factor.

$$\left(a+b\right)\left(a^{4}b^{7}+4a^{3}b^{8}+4a^{3}+6a^{2}b^{9}+4ab^{10}+4ab^{2}+b^{11}+8ba^{2}\right)$$

Consider a^{4}b^{7}+4a^{3}b^{8}+4a^{3}+6a^{2}b^{9}+4ab^{10}+4ab^{2}+b^{11}+8ba^{2}. Consider a^{4}b^{7}+4a^{3}b^{8}+4a^{3}+6a^{2}b^{9}+4ab^{10}+4ab^{2}+b^{11}+8ba^{2} as a polynomial over variable a.

$$b^{7}a^{4}+\left(4b^{8}+4\right)a^{3}+\left(6b^{9}+8b\right)a^{2}+\left(4b^{10}+4b^{2}\right)a+b^{11}$$

Find one factor of the form b^{l}a^{o}+w, where b^{l}a^{o} divides the monomial with the highest power b^{7}a^{4} and w divides the constant factor b^{11}. One such factor is a+b. Factor the polynomial by dividing it by this factor.

$$\left(a+b\right)\left(a^{3}b^{7}+3a^{2}b^{8}+4a^{2}+3ab^{9}+4ab+b^{10}\right)$$

Consider a^{3}b^{7}+3a^{2}b^{8}+4a^{2}+3ab^{9}+4ab+b^{10}. Consider a^{3}b^{7}+3a^{2}b^{8}+4a^{2}+3ab^{9}+4ab+b^{10} as a polynomial over variable a.

$$b^{7}a^{3}+\left(3b^{8}+4\right)a^{2}+\left(3b^{9}+4b\right)a+b^{10}$$

Find one factor of the form \left(ba\right)^{w}+w, where \left(ba\right)^{w} divides the monomial with the highest power b^{7}a^{3} and w divides the constant factor b^{10}. One such factor is a+b. Factor the polynomial by dividing it by this factor.

$$\left(a+b\right)\left(a^{2}b^{7}+2ab^{8}+4a+b^{9}\right)$$

Rewrite the complete factored expression.

$$a^{5}\left(a^{2}b^{7}+2ab^{8}+4a+b^{9}\right)\left(a+b\right)^{7}$$

Evaluate

$$a^{5}\left(a+b\right)^{7}\left(\left(a+b\right)^{2}b^{7}+4a\right)$$