Im very rusty heres my problem, please help thanks!(adsbygoogle = window.adsbygoogle || []).push({});

The radius of a sphere is expanding at the rate of 1 meter/min. At t=0 the radius is 1. In earch case, find the requested function and sketch the curve.

a)The surface area of the sphere as a function of the time;

For this i took: dR/dt = 1 m/min

A=4*Pi*r^2

dA/dt=8*pi*r*dR/dt

dA/dt = 8*pi*r <--- if this is right how do i sketch this graph as a function of time??

my graph points that i ploted were (0,8pi),(1,16pi),(2,24pi) etc... but this is confusing me because at t=0 radius is 1... is my x-axis supposed to be time or radius someone help me im confused..

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# Homework Help: Help, im rusty on first homework question!

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