1 + 2 + 3 + ... + x = 55

=> [ x(x+1) ] : 2 = 55

=> x(x+1) = 110

Ta thấy 10 . 11 = 110

=> x = 10

Vậy x = 10

Vì 4^x=64 mà 4^3 =64 nên x =3

        Đáp số :3

k)2^x+1.2²⁰¹⁴ =2²⁰¹⁵ 

2^x.2.2²⁰¹⁴=2²⁰¹⁵

2^x.2²⁰¹⁵=2²⁰¹⁵

2^x=2²⁰¹⁵:2²⁰¹⁵

2^x=1

Suy ra x=0

Rewrite as directed

1 Minh likes korean film better than Chunese film. - Minh prefers ..........

2 Shall we go out for a walk now? - Let's........

3 Reading books is more broing than watching TV Watching TV is more

a) 2,7 - x = 1,14

x = 2,7 - 1,14 

x = 1,56

2) x = 0,6 +4,6 - 1,5

x = 5,2 - 1,5

x = 3,7

99+1=100