Question 296390
1. A box with a square base has a surface area (including the top) of 3m^2.
 Express the volume V of the box as a function of the width w of the base.
Let h = the height of the box
S.A:
 2(w^2) + 4(wh) = 3
4wh = 3 - 2w^2
h = {{{(3-2w^2)/(4w)}}}
Vol
v = L*W*h
square base so
v = w^2*h
Replace h with {{{(3-2w^2)/(4w)}}}
v = w^2({{{(3-2w^2)/(4w)}}})
Cancel w
v = w({{{(3-2w^2)/4}}})
v = {{{(3w-2w^3)/4}}}
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2. A stone is thrown into a lake and t seconds after the splash the diameter
 of the circle of ripples is t meters.
a)Express the circumference C of this circle as a function of t.
{{{C = pi*t}}}
b)Express the area A of this circle as a function of t.
{{{A = pi*(.5t)^2}}}
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