document.write( "Question 32301: A Regualr polygon of n sides inscribed in a circle of radius r has 3r squared. What is the value of n? \n" ); document.write( "
Algebra.Com's Answer #20162 by venugopalramana(3286)![]() ![]() You can put this solution on YOUR website! A Regualr polygon of n sides inscribed in a circle of radius r has 3r squared. What is the value of n? \n" ); document.write( "YOU MEAN AREA =3R^2...ASSUMING SO... \n" ); document.write( "THERE WILL BE N TRIAGLES WHEN N VERTICES ARE JOINED TO THE CENTRE OF THE CIRCUM CIRCLE. \n" ); document.write( "SO EACH RIANGLE HAS AREA OF 3R^2/N \n" ); document.write( "NOW AREA OF EACH TRIANGLE IS GIVEN BY 0.5*R^2*SIN(X)...WHERE X IS THE ANGLE SUBTENDED BY ONE SIDE OF REGULAR POLYGON AT CENTRE OF CIRCUMCIRCLE. \n" ); document.write( "HENCE 0.5*R^2*SIN(X)=3R^2/N \n" ); document.write( "SIN(X)=3/(N*0.5)= 6/N \n" ); document.write( "NOW IF THERE ARE N SIDES THEN EACH SIDE SUBTENDS 360/N ANGLE AT CENTRE .HENCE \n" ); document.write( "X=2PI/N...OR....N=2PI/X \n" ); document.write( "SIN(X)=6*X/2PI=3X/PI \n" ); document.write( "WE FIND THAT AT X=30...OR...PI/6,WE HAVE SIN(X)=SIN(30)=SIN(PI/6)=0.5 \n" ); document.write( "AND 3X/PI=(3*PI)/(6*PI)=0.5 \n" ); document.write( "HENCE X=PI/6 IS THE SOLUTION \n" ); document.write( "HENCE N=2PI/X=(2PI)/(PI/6)=2*6=12 \n" ); document.write( "HENCE THE REGULR POLYGON IS 12 SIDED \n" ); document.write( " |