Domain of f(x)=sqrt(1+2x)
domain of f '(x)=1/sqrt(1+2x).........do not understand to do this one..
A minor (but important) change in your first answer . . .
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We include the
That prime-mark is distracting, but we can ignore it.
Since is under a square root, it must be positive or 0.
But since it is in the denominator, it cannot equal 0.
Hence, we have: .
Basically whenever you have a continous function on [a,b] and differenciable at (a,b) then the derivative does not exist at 'a' and 'b'. Do you see why? One of the conditions that implies a function is not differenciable is when it fails to be countinous. Note whenever you have a continous function on [a,b] then it is continous from the right at 'a' and continous from the left at 'b' but it is not fully continous.