Question #faa9f

1 Answer
Oct 5, 2017

dy/dx=((sec^2(x-y))(3+x^2)^2+(y)(2x))/((3+x^2)+(sec^2(x-y))(3+x^2)^2)dydx=(sec2(xy))(3+x2)2+(y)(2x)(3+x2)+(sec2(xy))(3+x2)2

Explanation:

tan(x-y)=y/(3+x^2)tan(xy)=y3+x2

Take the derivative of both sides.

d/dx(tan(x-y))=d/dx(y/(3+x^2))ddx(tan(xy))=ddx(y3+x2)

Solve.

d/dx(tan(x-y))=(1-dy/dx)(sec^2(x-y))ddx(tan(xy))=(1dydx)(sec2(xy))

d/dx(y/(3+x^2))=((3+x^2)(dy/dx)-(y)(2x))/(3+x^2)^2ddx(y3+x2)=(3+x2)(dydx)(y)(2x)(3+x2)2

Now we know:

(1-dy/dx)(sec^2(x-y))=((3+x^2)(dy/dx)-(y)(2x))/(3+x^2)^2(1dydx)(sec2(xy))=(3+x2)(dydx)(y)(2x)(3+x2)2

We can simplify

(1-dy/dx)(sec^2(x-y))(3+x^2)^2=((3+x^2)(dy/dx)-(y)(2x))(1dydx)(sec2(xy))(3+x2)2=((3+x2)(dydx)(y)(2x))

((sec^2(x-y))(3+x^2)^2-(dy/dx)(sec^2(x-y))(3+x^2)^2)=((3+x^2)(dy/dx)-(y)(2x))((sec2(xy))(3+x2)2(dydx)(sec2(xy))(3+x2)2)=((3+x2)(dydx)(y)(2x))

((sec^2(x-y))(3+x^2)^2+(y)(2x))=((3+x^2)(dy/dx)+(dy/dx)(sec^2(x-y))(3+x^2)^2)((sec2(xy))(3+x2)2+(y)(2x))=((3+x2)(dydx)+(dydx)(sec2(xy))(3+x2)2)

((sec^2(x-y))(3+x^2)^2+(y)(2x))=(dy/dx)((3+x^2)+(sec^2(x-y))(3+x^2)^2)((sec2(xy))(3+x2)2+(y)(2x))=(dydx)((3+x2)+(sec2(xy))(3+x2)2)

((sec^2(x-y))(3+x^2)^2+(y)(2x))/((3+x^2)+(sec^2(x-y))(3+x^2)^2)=dy/dx(sec2(xy))(3+x2)2+(y)(2x)(3+x2)+(sec2(xy))(3+x2)2=dydx

Depending on how simplified the answer needs to be, this is technically the solution.