Question 119372
The formula for the surface are of a sphere is A=4pir^2. A square sticker of side x is placed on a ball of radius 3x. What is the surface area of the not covered by the sticker? Please Write your answer in factored form.
:
Sphere area - sticker area = uncovered area
{{{4*pi*r^2}}} - {{{x^2}}}
Substitute 3x for r
{{{4*pi*(3x)^2 - x^2}}}
{{{4*pi*9x^2 - x^2}}}
Multiply 9*4
{{{36*pi*x^2 - x^2}}}
Factor out x^2
{{{x^2(36*pi - 1)}}}