Qualification > Math

Maths help!

(1/4) > >>

tmisterr:
if any one has the pure maths 1 text book for CIE, i need help with miscellaneous excersice 7 number 15, 16, and 17!

staceyboy3:
Could you tell me the questions cause i bet i don't have the same book as you.

astarmathsandphysics:
Yes better ifyou post the question

tmisterr:
The costs of a firm which makes climbing boots are of two kind:
-Fixed cost (plant rates, office expenses): $2000 per week;
-Production costs (material, labour): $20 for each pair of boots made.
Market research suggest that if they price the boots at $30 a pair they will sell 500 pairs a week, but that at $55 a apair they will sell none at all; and between these values the graph of sales against profit is a straight line.
If they price boots at $x pair (30<x<55) (inclusive) find expressions for
a) weekly sales,
b) the weekly reciepts
c) the weekly costs
assuming that just enought boots are made
hence showing that the weeklly profit, $P, is given by
P=-20x2+ 1500x-2400.
Find the price at which the boots should be sold to maximise the profit.

tmisterr:
Sketch the graph of an even function f(x) which has a derivative at every point.
 Let P be the point on the graph for which x=p (where p>0). Draw the tangent at P on your sketch. Also draw the tangetn at the point P' for which x=-p.
a) what is the relationship between the gradient at P' and the gradient at P? what can you deduce about the relationship between the gradient f'(p) and f'(-p)? what does this tell you about the derivative of an even function?
b) show the derivative of an odd function is even.

Navigation

[0] Message Index

[#] Next page