In a `DeltaABC, c^4-2(a^2+b^2)c^2+a^4+a^2b^2+b^4=0` then the acute angle `C=`

Delta ABC,c^(4)-2(a^(2)+b^(2))c^(2)+a^(4)+a^(2)b^(2)+b^(4)=0 then the acute angle C=

In /_ABC, if c^(4)-2(a^(2)+b^(2))c^(2)+a^(4)+a^(2)b^(2)+b^(4)=0 then

In an acute angled Delta ABC , if a^(4) + b^(4) +c^(4) = 2c^(2) (a^(2) + b^(2)) then the angle C is

In Delta ABC , if c^(4) - 2 (a^(2) + b^(2) ) c^(2) + a^(4) +a^(2) b^(2) + b^(4) = 0

If in DeltaABC,a^(4)+b^(4)+c^(4)=2a^(2)(b^(2)+c^(2)) , then angleA is

In a Delta ABC, a ^(4)+b^(4) + c^(4) = 2b^(2)c^(2)+2a^(2)b^(2), " then B"=

If a, b, c are the sides of the triangle ABC such that a^(4) +b^(4) +c^(4)=2c^(2) (a^(2)+b^(2)), then the angle opposite to the side c is-