Question

A + b > c dan c + d > a maka....
A. -b < a < d
B. c - a < d < b
C. d < c < b
D. a - d < c < a + b
E. b + c < a < c+ d

Answer 1

Jawaban:

a + b > c

Kita anggap

a = 2

b = 3

c = 1

2 + 3 > 1 (memenuhi a + b > c)

1 + d > a

1 + d > 2

anggap

d = 4

1 + 4 > 2 (memenuhi c + d > a)

jadi :

a = 2

b = 3

c = 1

d = 4

A

-b < a < d = -3 < 2 < 4 (benar)

B

c - a < d < b = 1 - 2 < 4 < 3 (salah)

C

d < c < b = 4 < 1 < 3 (salah)

D

a - d < c < a + b = 2 - 4 < 1 < 2 + 3 (benar)

E

b + c < a < c + d = 3 + 1 < 2 < 1 + 4 (salah)