va rog repede 26 si de la efectuati a si b

= > 2 / 3 = 4 / 6
= > 14 / 5 = 28 / 10
= > 4 / 18 = 2 / 9
= > 12 / 5 = 24 / 10
Ex 27:
a ) 2 / 3 ^ 2 = 4 / 9
2 / 1 : 4 / 9 = 2 / 1 x 9 / 4 = 1 / 1 x 9 / 2 = 9 / 2
11 / 5 : 11 / 10 = 11 / 5 x 10 / 11 = 1 / 1 x 2 / 1 = 2 / 1
9 / 2 + 2 / 1 = 9 / 2 + 4 / 2 = 13 / 2 = 6 , 5
b ) 3 / 1 - 1 / 3 ^2 = 9 / 3 - 1 / 3 = 8 / 3 ^ 2 = 64 / 9
2 / 1 - 1 / 2 ^2 = 4 / 2 - 1 / 2 = 3 / 2 ^2 = 9 / 4
1 1/2 ^2 = 3 / 2 ^ 2 => 9 / 4
64 / 9 + 9 / 4 = 256 / 36 + 81 / 36 = > 337 / 36
337 / 36 - 9 / 4 = 337 / 36 - 81 / 36 = 256 / 36 = 128 / 18 => 64 / 9

Cocirmariadenis Cocirmariadenis · Answer 2 · 2018-03-24T11:33:09+02:00

26)

2/3 = a/6 ⇒ 3× a = 2×6 ⇒ a = 12 : 3 ⇒ a = 4 ⇔ 2/3 = 4/6

b/5 = 28/10 ⇒ 10 × b = 5 × 28 ⇒ 10×b = 140 ⇒ b = 240 : 10 ⇒ b = 24 24/5 = 28/10

4/c = 2/9 ⇒ 2× c = 4× 9 = c = 36 : 2 ⇒ c = 18 ⇔ 4/18 = 2/9

12/5 = 24/d ⇒ 12 d = 24 × 5 = 120 ⇒ d = 120 : 12 = 10 ⇔ 12/5 = 24/10

27)

a) 2 : 4/9 + 11/5 : 11/10 = 2 × 9/4 + 11/5 × 10/11 = 9 /2 + 2 = 9/2 + 4/2 = 13/2 = 6 intregi si 1/2

b) ( 3 - 1/3 ) ² + ( 2 - 1/2 ) ² - ( 1 intreg si 1/2 ) ²

3 - 1/3 = 9/3 - 1/3 = 8/3

2 - 1/2 = 4/2 - 1/2 = 3/2

1 intreg si 1/2 = ( 1 × 2 + 1) /2 = 3/2

( 8/3) ² + ( 3/2)² - ( 3/2)² = 64/9 + 9/4 - 9/4 = 64/9 = 7 intregi si 1/9= 7,(1)