Hello everyone, I had to be stuck with a Maths teacher from hell...
I was taught how to get the inverse of the following: 2x2 + 8x - 7 show at f-1(2)
I understood the computations and interchanging and how it arrived at: 2y2 + 8y - 9 = 0
However, my teacher used b2 - 4ac to arrive at 64 - 72 = -8, which is where my problem begins.
I would like to know what testing for a perfect square has got to do with the inverse and how it proves it is or isn't an inverse.
Also would like to know if it is bijective.
I would be very greatful for explanations, my teacher doesn't explain anything and i think you guys are way better teachers.