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anonymous
 5 years ago
Find the surface area of a sphere of radius r, using calculus.
anonymous
 5 years ago
Find the surface area of a sphere of radius r, using calculus.

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0that would be amazing if you could help! :)

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0so the equation of a circle having center (0,0) is x^2+y^2+r^2

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0oh surface area not volume one sec. let me rething my strategy

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Use the formula for the surface area of a general equation revolved around the xaxis. If you start with x^2 + y^2 = r^2, and your function is y, then f(x) = sqrt(r^2x^2). The formula for the surface area of revolution is, in this case, \[SA = 2 \pi* \int\limits_{r}^{r} \ \ f(x) * \sqrt{1+f(x)^2}\] Integrate and simplify.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sorry, inside the root of the integrand it should be f'(x)^2.

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0what is the circumference of sphere

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Thanks QuantumModulus, that helped a lot!!

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0have you done trig substition yet?

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0I think you may have to do in one of the steps

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0nvm it is a simple integration

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0ok but i think was suppose to get 4pi*r^2

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0let me know what you get?

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0ok it is 4*pi*r^2 because the semicirlce is being revolved about the x axis

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0ignore the extra stuff on that attachment

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.0I have to go. You can check your work with the attachment just ignore the But part. goodnight
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