This is the question from memory, i may have potentially made a mistake, but i do believe it is correct. This should all be done without a calculator.
For the equation , find the minimum value for 'a' where y > 0 for all of x. Leave in exact answer form.
Note, on a previous question i was asked to show (without a calculator) that , so that may be relevant.
In fact, i would appreciate if you could explain the second question too.