Question

Сократить дробь

1) 4а+8b

______

4a

2) x^2 - 25

_______

2x-10

3) 6^5 - b^3

________

b^2-b^4

4) 4p^2-28pq+49q^2

__________

49q^2 - 4p^2

Answer 1

$\frac{4a+8b}{4a}=\frac{4(a+2b)}{4a}=\frac{a+2b}{a}$

$\frac{x^2-25}{2x-10}=\frac{(x-5)(x+5)}{2(x-5)}=\frac{x+5}{2}$

$\frac{b^5-b^3}{b^2-b^4}=-\frac{b^3(b^2-1)}{b^2(b^2-1)}=-\frac{b^3}{b^2}=-b$

$\frac{4p^2-28pq+49q^2}{49q^2-4p^2}=-\frac{(2p-7q)^2}{(2p-7q)(2p+7q)}=\frac{7q-2p}{2p+7q}$