[" 99.If "(x)/(y)=(1)/(3)," then "(x^(2)+y^(2))/(x^(2)-y^(2))=?],[[" (a) "-(10)/(9)," (b) "(5)/(4)]]

If (x)/(y)=(1)/(3), then (x^(2)+y^(2))/(x^(2)-y^(2))=?(a)-(10)/(9) (b) (5)/(4)(c)-(5)/(4)(d)-(5)/(3)

If   x/y = 1/3 , then ( ( x^2 + y^2 )/( x^2 - y^2 ) ) is equal to

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

Evaluate (3x^(4)y^(2))(2x^(2)y^(3)) for x = 1 and y = 2.

"Find the value of "(x+y)," if "(x+(y^(3))/(x^(2)))^(-1)-((x^(2))/(y)+(y^(2))/(x))^(-1)+((x^(3))/(y^(2))+y)^(-1)=(1)/(3)

If x^2=y^3 , then prove that (x/y)^(3/2)+(y/x)^-(2/3)=x^(1/2)+y^(1/3) .

If x and y are of same sign,then the value of (x^(3))/(2)cos ec^(2)((1)/(2)(tan^(-1)x)/(y))+(y^(3))/(2)sec^(2)((1)/(2)(tan^(-1)y)/(x)) is equal to (x-y)(x^(2)+y^(2)) (b) (x+y)(x^(2)-y^(2))(x+y)(x^(2)+y^(2))*(d)(x-y)(x^(2)-y^(2))