Respostas
a) 2x²/5a : x/15a =
2x²/5a · 15a/x =
30x²a/5ax = 6x
b) x²y/m³n : xy²/m²n =
x²y/m³n . m²n/xy² =
x²ym²n/m³nxy² = x/ym
c) 5p⁵q/2a⁴ : 25p⁴q/2a⁵ =
5p⁵q/2a⁴ . 2a⁵/25p⁴q =
10p⁵a⁵/50a⁴p⁴q = pa/5q
d) 21t⁴/12b : 7t⁵b/2 =
21t⁴/12b . 2/7t⁵b =
42t⁴/84t⁵b² = 1/2tb²
e) 12a²/8xy : 6/axy =
12a²/8xy . axy/6 =
12a³xy/48xy = a³/4
f) x/(a - 1) : x²/(a² - 1) =
x/(a - 1) . (a² - 1)/x² =
x(a² - 1)/x²(a - 1) =
x(a + 1)(a - 1)/x²(a - 1) = (a + 1)/x
g) (a + b)/(a² - b²) : a/(a² - ab) =
(a + b)/(a² - b²) . (a² - ab)/a =
(a + b)(a² - ab)/a(a + b)(a - b) =
(a² - ab)/a(a - b) =
(a² - ab)/(a² - ab) = 1
h) 2y⁴/(3a⁵ + 9a⁴) : 6y³/(3a + 9) =
2y⁴/(3a⁵ + 9a⁴) . (3a + 9)/6y³ =
2y⁴(3a + 9)/6y³(3a⁵ + 9a⁴) =
2y⁴(3a + 9)/6y³[a⁴(3a + 9)] = y/3a⁴
i) (a² - 2a + 1)/x² : (a² - 1)/x =
(a² - 2a + 1)/x² . x/(a² - 1) =
(a - 1)(a - 1)/x² . a/(a + 1)(a - 1) =
a(a - 1)(a - 1)/x²(a + 1)(a - 1) = a(a - 1)/x²(a + 1)
j) (t - 2)/(5p + 25) : (2t - 4)/(p² - 25) =
(t - 2)/(5p + 25) . (p² - 25)/(2t - 4) =
(t - 2)(p² - 25)/(5p + 25)(2t - 4) =
(t - 2)(p + 5)(p - 5)/5(p + 5).2(t - 2) =
(p - 5)/5.2 = (p - 5)/10