By making the substitution u =ln x show that the following equation has exactly one real-number solution:

-12/ln x +ln x^4 = -9

2 answers

well, do the math:

-12/u + 4u = 9
4u^2-9u-12=0

solve for u and then consider the domain of ln x.
I don't understand how you got those equations! Pleaseee help