How to solve this equation?

HOW are you supposed to solve it ? It is not an easy equation to solve ; there is only one solution in real numbers. I am not going to go into a complex solution which you probably are not going to understand.

You can do it most simply by putting in various values for λ, and finding ones which make the expression 0.

I can tell you that the real solution is between -1.7 and -1.8. You can refine that further by trying values between those two to find whether -1.71 is nearer, or -1.79, and so on.

put a sock near the power button then 0 will cross link between the others socks nearby

Seems tough.. what this stands for λ ?