Solving Y=\sqrt{x}(x-1) Derivitive

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To solve the derivative of y = √x(x - 1), first express √x as x^(1/2) and distribute it. The derivative can be found using the product rule, resulting in (x - 1)(1/2√x) + √x. There are multiple correct methods to arrive at the same answer, emphasizing the flexibility in calculus approaches. It is recommended to avoid using mixed fractions for clarity, opting instead for improper fractions. Overall, the discussion highlights different strategies for deriving functions involving square roots.
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How do I deal with the square root in y = \sqrt{x}(x - 1)?
 
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\sqrt{x} = x^{(\frac{1}{2})}

Distribute and take it away.

Also, remember that a^x*a^y=a^{(x+y)}
 
You know the simple formula for deriving powers of x, right? Well, \sqrt{x}=x^{\frac{1}{2}}

EDIT: I was slow. Sorry, I didn't mean chain, I meant distrubution for derivation (didn't know what you call it in English).
 
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Can I get any further that here?

\left(x - 1\right)\left(\frac{1}{2\sqrt{x}}\right) + \sqrt{x}
 
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You're making it more complicated than neccessary.

Distribute the \sqrt{x} then take the derivative.

Ok, your way works, but I wouldn't do it that way. That's the beauty of it though, many correct ways to get the same answer.
 
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1\frac{1}{2}x^{\frac{1}{2}} - \frac{1}{2}x^{-\frac{1}{2}}

correct?
 
First part is incorrect, second part is correct.
 
Hmm I don't see how :frown:

x^{\frac{1}{2}} \cdot x^1 = x^{1.5} so doesn't that become 1.5 \cdot x^{\frac{1}{2}}?
 
Oh, ok. You were righting a mixed fraction. It would be best to write 1.5 as \frac{3}{2}

Try not to use mixed fractions, they get too confusing. Use improper ones.

For example: take the derivative of 3\frac{1}{2}\frac{5}{7}x^4 with respect to x. Make sense?
 
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  • #10
Jameson said:
Oh, ok. You were righting a mixed fraction. It would be best to call 1.5 \frac{3}{2}

Try not to use mixed fractions, they get too confusion. Use improper ones.

Thanks for the tip and your help (Berislav too) :smile:
 
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