Question

(a^4-10a^2+169)/(a^2+6a+13) упростите выражение

Answer 1

$\displaystyle \frac{a^4-10a^2+169}{a^2+6a+13} =\frac{a^4+6a^3-6a^3+13a^2-13a^2-10a^2+169}{a^2+6a+13} =\\\\=\frac{a^4+6a^3+13a^2-6a^3-23a^2+169}{a^2+6a+13} =\\\\=\frac{a^2(a^2+6a+13)-6a^3-36a^2+36a^2-78a+78a-23a^2+169}{a^2+6a+13} =\\\\=\frac{a^2(a^2+6a+13)-6a^3-36a^2-78a+13a^2+78a+169}{a^2+6a+13} =\\\\=\frac{a^2(a^2+6a+13)-6a(a^2+6a+13)+13(a^2+6a+13)}{a^2+6a+13} =\\\\=\frac{(a^2+6a+13)(a^2-6a+13)}{a^2+6a+13} =a^2-6a+13$

Answer 2

$\frac{a^4-10a^2+169}{a^2+6a+13}= \frac{a^4+26a^2+169-36a^2}{a^2+6a+13}= \frac{(a^2+13)^2-36a^2}{ a^2+6a+13 }= \frac{(a^2+13-6a)(a^2+13+6a)}{ a^2+6a+13 }=a^2-6a+13$