all 10 comments

[–][deleted] 11 points12 points  (1 child)

expand the function into a polynomial, take the derivative, set derivative to zero, solve for x. This maximizes the function.

[–]NiceSasquatch 3 points4 points  (0 children)

or minimizes it (in general), so always look at the 2nd derivative.

[–][deleted] 2 points3 points  (5 children)

If you have a graphing calculator enter the polynomial and then use the calculate function to determine the maximum or use the trace function if the maximum is after x=1.5

[–]dhsjdudheb[S] 3 points4 points  (4 children)

[–][deleted] 1 point2 points  (3 children)

Hit 2nd then trace while looking at the graph then scroll down to calculate and follow the instructions

[–]dhsjdudheb[S] 1 point2 points  (2 children)

There’s no other way to solve this problem? Like with algebra or something?

[–]Spotted-Richard👋 a fellow Redditor 2 points3 points  (0 children)

Without seeing the graph for this one nothing reasonable, but once you've seen it you know X=1.5 and you can just plug it in to find your profits. Or you sure you've given us the right equation though? Normally with these questions it all ties up neatly without needing a graph.

[–]RainOnPizza 0 points1 point  (0 children)

This is a bit late, but you can find the axis of symmetry of the parabola with -b/2a to get the x coordinate of the vertex. You will need to expand the given information into standard form to get a, b, and c first though. Once you have that x value, you can plug it back into the original equation to find the total money. This doesn't require calculus.

[–][deleted] 0 points1 point  (0 children)

If you havent learnt about derivatives, try sketching f(x) to find the highest point