Weird 'calculus' question (1 Viewer)

[leehuan]

This was in my calculus set of questions, not my algebra. So I'm not motivated to use vectorial methods.



It got placed under IMVT and extreme value theorem etc. But I have no idea how to use limits or whatever to tackle this question. Honestly this is what I would've done.

1. Gradient of the line perpendicular to it.
2. The above line passes through the origin
3. Simultaneous equations

Is there a more clever way to do this?

 

[InteGrand]

This was in my calculus set of questions, not my algebra. So I'm not motivated to use vectorial methods.



It got placed under IMVT and extreme value theorem etc. But I have no idea how to use limits or whatever to tackle this question. Honestly this is what I would've done.

1. Gradient of the line perpendicular to it.
2. The above line passes through the origin
3. Simultaneous equations

Is there a more clever way to do this?

The reason for using squared-distance is that it is more convenient to work with as it does not have a square root, and it yields the same answer.