Im doing a proof of the derivative of cot(x) with the limit definition

[pale zinc]

here, the numerator should be:
cos(x+h)sin(x)-cos(x)sin(x+h)

[young knoll]

omg ur right

ty

[pale zinc]

urwelcome

[young knoll]

like this? and idk how to continue

[pale zinc]

you can use the formula
sin(a-b) = sin(a)cos(b)-cos(a)sin(b)
for the numerator
then it becomes sin(-h) = -sin(h)
then you can apply the formula
lim(x->0,sin(x)/x) = 1

[young knoll]

holy

thats so smart

didnt think of it cuz a is (x+h)

ty

[pale zinc]

urwelcome

[young knoll]

is this correct? @pale zinc

I think it is

[pale zinc]

yes

[young knoll]

cool, ty for the help :D