Question

If e^x + e^y = e^x+y, then `"dy"/"dx"` is:

Options

• e^y−x

• e^x+y

• −e^y−x

• 2e^x−y

Answer 1

−e^y−x

Explanation:

e^x + e^y = e^x+y

e^−y + e^−x = 1

Differentiating w.r.t. x:

`-"e"^(-"y") "dy"/"dx" - "e"^(-"x")` = 0

`"dy"/"dx"` = −e^y−x