伐數分式及公式2(請盡快回答)

3.
(c)
2q(m - n)³ / 6q²(m- n)²
= (m - n) / 3q


====
4.
(a)
4 / (2p - 8q)
= 4 / 2(p - 4q)
= 2 / (p - 4q)

(b)
(3n² + 15n) / 9n
= 3n(n + 5) / 9n
= (n + 5) / 3

(c)
12ab / (18a² - 6ab)
= 12ab / 6a(3a - b)
= 2b / (3a - b)


====
5.
(a)
(6b + 2a) / (4a - 6b)
= 2(3b + a) / 2(2a - 3b)
= (a + 3b) / (2a - 3b)

(b)
(n - m) / 2m - 2n
= -(m - n) / 2(m - n)
= -1 / 2

(c)
(6xz - 4yz) / (15x - 10y)
= 2z(3x - 2y) / 5(3x - 2y)
= 2z / 5


====
1.
(a)
2 / 8a
= 1 / 4a

(b)
7x / x²
= 7 /x

(c)
c² / c³d
= 1 / cd


====
2.
(a)
2a / 6ab
= 1 / 3b

(b)
12xy² / 3x²y
= 4y / x

(c)
5pq³ / 20q²r²
= pq / 4r²