9*(4^-1/x)+5*(6^-1/x)<4*(9^-1/x)

Question

9*(4^-1/x)+5*(6^-1/x)<4*(9^-1/x)<br>

Answer 1

9/4x+5/6x<4/9x<br>9/4x+5/6x-4/9x<01<br>(81+30-16)/36x<0<br>95/36x<0<br>95>0⇒36x<0⇒x<0<br>x∈(-∞;0)