" (iii) "x^(4)-y^(4)

The solution of the differential equation (dy)/(dx)+(x(x^(2)+3y^(2)))/(y(y^(2)+3x^(2)))=0 is (a) x^(4)+y^(4)+x^(2)y^(2)=c (b) x^(4)+y^(4)+3x^(2)y^(2)=c (c) x^(4)+y^(4)+6x^(2)y^(2)=c (d) x^(4)+y^(4)+9x^(2)y^(2)=c

If log_5 ((x^(4)+y^(4))/(x^(4)-y^(4))) =2 , show that (dy)/(dx) = (12x^(3))/(13y^(2))

Find y'' if x^(4) + y^(4) = 16 .

Factorise : 16x^(4)-y^(4)

If x-y=3 and xy=10, then find x^(4)+y^(4).

If x+y=3 and xy=2, then find x^(4)+y^(4)