Find mean proportional of `(x+y)/(x-y),(x^2-y^2)/(x^2y^2)`

(x-y^2x)dx=(y-x^2y)dy

Choose the correct alternative answer for each of the following question. What is the mean proprotion of (x+y)^2 and (x-y)^2 ?

cos^(- 1)((x^2-y^2)/(x^2+y^2))=loga find dy/dx

Find the value of (x+y),if 5x-2y=10,x+8y=26

If x/y=4/5 then find the value of the ratio (3x^2+y^2)/(3x^2-y^2) .

Find the value of (x-y), if 2x-5y=5,5x-8y=14

If x/y=13/6 then find the value of (2x^2+5y^2)/(2x^2-5y^2)