ATAR-wise, it would be a good strategy for you to improve your weakest subject
However, if you do find the effort you put into english not correlating with the improvement of your marks, then prioritise other subjects you'll need to improve
in highschool, whenever I got a system of linear equations with 3 variables, I just did basic operations randomly and HOPE I'd end up with the right answer
remember the function asymptotically approaches y=1 as x tends to +ve/-ve infinity
that does not show us any infomation about its behaviour when x is finite, so it could cross it at some finite value
does that make sense?