The lengths of the sides a, b, c of a ΔABC are connected by the relation a^2 + b^2 = 5c^2. The angle between medians drawn to the sides 'a' and 'b' is -Maths 9th

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Answer :

Let median through C be CF. AF=FB=c2   CF=122(a2+b2)−c2−−−−−−−−−−−−√=3c2   CG=c where G is the centroid and GF=c2   34(a2+b2+c2)=M2a+M2b+M2c   9c22=M2a+M2b+9c24   c2=(23M2a)+(23M2b)   BC2=AG2+BG2   So medians through A and B are perpendicular.

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