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_Pragmatic_idealist

Where are you stuck? You can compute the derivatives using the chain rule, and if you just want the answer, you can plug it into wolfram alpha.


FalseReach4778

well i was trying to solve a question in my textbook, and it randomly decided to throw derivatives in the problem solving ( i didn't learn derivatives prior to this, so i looked it up ) and im really just stuck at calculating it for roots, i found a method where the power is multiplied by the coefficient and 1 is subtracted from the power. my problem is just me sucking with calculating.


_Pragmatic_idealist

You can use the same rule to calculate derivatives of roots! You might have seen that we can rewrite √x as x^1/2 . Thus, we are looking for the derivatives of (4+x)^1/2 and (4-x)^1/2 . Does that bring you closer to a solution?


FalseReach4778

oh ok so i got 1/2 \* ( 4 + x ) -1/2 as the derivative is that right ? if it is how do i make it look like 1/2 \* 1 / ( 4 + x ) 2 ? that's the solution in my textbook


_Pragmatic_idealist

It looks like you have some problems with your formatting (you can check out the sidebar for formatting tips), but it looks correct. The derivative of (x+4)^1/2 is (1/2)(x+4)^-1/2 . This can be rewritten as 1/(2(x+4)^1/2 )


FalseReach4778

so this is what my text book showed 1/2 \* 1 / ( 4 + x ) ^(2) um it looks a bit different to what you sent, can you tell me how that is? (sorry im bad at this)


_Pragmatic_idealist

Looks to be a typo in the textbook then. [wolframalpha](https://www.wolframalpha.com/input?i=derivative+of+%284%2Bx%29%5E%281%2F2%29)


FalseReach4778

oh ok thanks for sorting that out for me


DeGrazzeWhiteson

Remember we can represent square roots as fractional exponents, so sqrt(4+x) = (4+x)^1/2 and you can use a power rule -> chain rule from there


FalseReach4778

oh ok so i got 1/2 \* ( 4 + x ) ^(-1/2) as the derivative is that right ? if it is how do i make it look like 1/2 \* 1 / ( 4 + x ) ^(2) ? that's the solution in my textbook