Question

How do you find the derivative of 1+2^(4-t) ?

Answer 1

the one will disappear. you can set 4-t=u so you have 2^u

Answer 2

then you would get ln (2)*2^u*du
ln (2)*2^(4-t)*(-1)
-ln (2)(2^(4-t))

Answer 3

Let u = 4 - t
du/dx = -1
dy/dx = 2^(4-t) ln 2 (-1) = -(ln2)[2^(4-t)]

Answer 4

and the answer gets repeated.