I dont understand the working out in the first line (1 Viewer)

[An0nyM0usUseR455]

Like I understand both curves intersect at x as they are the inverse and its way too hard to find the inverse but using x instead of the inverse wont give u the correct shaded area

 

[STBAccuracy]

I've attached some working, hmu if there are still any outstanding issues.

 

[An0nyM0usUseR455]

I've attached some working, hmu if there are still any outstanding issues.

Thanks for the brilliant answer !!!

I get it now