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Grade 11Differential Calculus

Let ABCD be a rectangle with AB=a and BC=b.Suppose r1 is the radius of the circle passing through A and B and touching CD ; r2 is the radius of the circle passing through B and C and touching AD then prove that

r1=a2+4b2/8b and r2=b3+4a2b/8ab

Profile image of sindhuja P
16 Years agoGrade 11
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1 Answer

Profile image of Badiuddin askIITians.ismu Expert
ApprovedApproved Tutor Answer16 Years ago

Dear sindhuja


6886-2351_7662_untitled.JPG

in triangle AOD

AO2 =AD2 +OD2

r12  = a2/4  + (b-r1)2

r12  = a2/4  +  b2 +r1-2br1 

r1=a2+4b2/8b

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