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Need help with further differentiation please!

4xx3\frac{4x}{x^3} - 3x1/2x3\frac{3x^1/2}{x^3}

First time using latex, anyway please help.
(edited 11 years ago)
Reply 1
4xxx2y=2xy\displaystyle \frac{4x}{\partial x} x^2y = 2xy
Reply 2
Original post by Tynos
4xx3\frac{4x}{x^3} - 3x1/2x3\frac{3x^1/2}{x^3}

First time using latex, anyway please help.


Write it in the form:

4xp3xq4x^p-3x^q where you have to find p and q.

After doing so, differentiate.

Hint:

4x=4x1\frac{4}{x}=4x^{-1}
Reply 3
I know lol, im stuck at the second part.
Hi, I don't know how to use the Math Editor so bear with me.
d/dx(x^p)=p*x^(p-1) provided p =/= 0
It's a fairly simple rule, the derivation is quite straightforward if you know binomial expansions.
If you use that with the hints above you can get an answer.
Reply 5
Im just stuck on this part 3x1/2x3\frac{3x^1/2}{x^3}
Reply 6
Original post by Tynos
Im just stuck on this part 3x1/2x3\frac{3x^1/2}{x^3}


123=52\frac{1}{2} - 3 = -\frac{5}{2}

so

3x12x3=3x52\dfrac{3x^{\frac{1}{2}}}{x^3} = 3x^{-\frac{5}{2}}

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