tim x biet (2/5)^x>(2/5)^3.(-2/5)^2

Đáp án:

Giải thích các bước giải:

$\left (\dfrac{2}{5} \right )^x>\left (\dfrac{2}{5} \right )^3 . \left (\dfrac{-2}{5} \right )^2$

$⇔\left (\dfrac{2}{5} \right )^x>\left (\dfrac{2}{5} \right )^3 . \left (\dfrac{2}{5} \right )^2$

$⇔\left (\dfrac{2}{5} \right )^x>\left (\dfrac{2}{5} \right )^5$

$⇔x>5$