12quad (x^(2)+y^(2)+(1)/(x^(2))+(1)/(y^(2))=4," then find the value of "x^(2)+y^(2)

if x^(2)+y^(2)+(1)/(x^(2))+(1)/(y^(2))=4 then find the value of x^(2)+y^(2)

If x^2+y^2+1/y^2+1/y^2=4 then find the value of x^2+y^2

If x=1, y=2 find the value of: x^2+y^2

if 2x+y=1 then find the maximum value of x^(2)y

If ((2x-y)/(x+2y))=(1)/(2), then find the value of ((3x-y)/(3x+y))

x>1,y>1 and (In x)^(2)+(In y)^(2)=In x^(2)+In y^(2), then find the maximum value of x ln y.

If y=(sin^(-1)x cos^(-1)((x^2)/2))/(1+x^2) then find the value of y(1/2) + y(1/sqrt2) + y(-1/2) + y(-1/sqrt2)