Hello I have a folllowing question Function A(r)=2*pi*r^{2}+6*pi*r. I has a an inverse function r(A)=(-6*pi+-sqrt(4*pi(9*pi+2r))/4*pi Calculate at what radius does the area of the cylinder equal 200. do i just make the function r(A)=200? Thanks
Last edited by dbag; May 27th 2019 at 05:15 AM.
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it should be $\displaystyle r=\frac{-6 \pi + \sqrt{4\pi (9 \pi +2A)}}{4 \pi } $ now replace $A=200$
Last edited by Idea; May 27th 2019 at 07:15 AM.
Originally Posted by dbag I has a an inverse function r(A)=(-6*pi+-sqrt(4*pi(9*pi+2r))/4*pi This is a very bad mistake. Understanding what a function is and isn't is SO fundamental. Please review the definition.