Symbolic Differentiation wrt time

I have such an expression;

(x(t) + y(t))^2

Where x and y are function of t How can I symbolically take the derivative of this expression with respect to t

Which has to result in 2[xx' + xy' + yx' + yy']

Answer 1

[Wayne King]

    syms t x(t) y(t)
    diff((x(t)+y(t))^2)

The above gives the output:

2*(x(t) + y(t))*(diff(x(t), t) + diff(y(t), t))

which is equivalent to what you have in your post.

[Mohammad]

hi, what about when we want to have upper degree derivatives of the same expression?

[Walter Roberson]

diff((x(t)+y(t))^2,t,3) %third derivative