Question

(1/а^2-ав -3в^2/а^4-ав^3 -в/а^3+а^2в+ав^2)*(в+а^2/а+в)

Answer 1

$1)frac{1}{a^{2}-ab} -frac{3b^{2}}{a^{4}-ab^{3}} -frac{b}{a^{3}+a^{2}b+ab^{2}}=frac{1}{a(a-b)}-frac{3b^{2}}{a(a^{3}-b^{3})}-frac{b}{a(a^{2}+ab+b^{2})}=frac{1}{a(a-b)}-frac{3b^{2}}{a(a-b)(a^{2}+ab+b^{2})}-frac{b}{a(a^{2}+ab+b^{2})}=frac{a^{2}+ab+b^{2}-3b^{2}-ab+b^{2}}{a(a-b)(a^{2}+ab+b^{2})} =frac{a^{2}-b^{2}}{a(a-b)(a^{2}+ab+b^{2})}= frac{a+b}{a(a^{2}+ab+b^{2})}$

$2)frac{a+b}{a(a^{2}+ab+b^{2})}*(b+frac{a^{2}}{a+b})=frac{a+b}{a(a^{2}+ab+b^{2})} *frac{ab+b^{2}+a^{2}}{a+b}=frac{1}{a}$