Year 11 - functions (1 Viewer)

[HazzRat]

This question is very insidious in that it looks easy but is somewhat difficult (or at least difficult to start off on). How do I solve it?

 

[cossine]

View attachment 37732
This question is very insidious in that it looks easy but is somewhat difficult (or at least difficult to start off on). How do I solve it?

Question is extremely easy. Basic substitution.

You need first find an expression for area. Hint introduce another variable "l".

Formulate the constraint, using x and "l".

Using substitution eliminate "l" in the formula for area by making it the subject in the constraint.

This gives area A.

b/c involves parabolas so are easy.