1.tim x biet (7x – 11) mũ 3=2mũ5 X 5mũ2 + 200 2.tinh (- 43 ) + ( – 19 )

1.

`(7x – 11)³ = 2^{5} X 5² + 200`

`⇔ (7x – 11)³ = 32 X 25 + 200`

`⇔ (7x – 11)³ = 800 + 200`

`⇔ (7x – 11)³ = 1000`

`⇔ 7x – 11 = ∛1000`

`⇔ 7x – 11 = 10`

`⇔          7x = 10 + 11`

`⇔          7x = 21`

`⇔             x = 21 : 7`

`⇔             x = 3`

Vậy x = 3

2.

(-43) + (-19) = (-43) – 19 = -62