Differentiaton

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How does one differentiation the addition of two functions? for example:

y= (5+4x)^3/2 + (5-4x)^3/2

What rule should I use for this?
 
I think it's just the differential of the sum of the two separate differentials.

eg y = 2x + 1

dy/dx = 2 + 0 = 2
 
badgermonkey said:
Differentiate each seperately eg:


6(5+4x)^1/2 - 6(5-4x)^1/2

Is the answer


Explanation sorry:

Differentiate the first term

(5+4x)^3/2 -> Power down in front, drop the power by one, and then times by the differentiation of the terms inside the brackets

Added to

The same for the second one. However as multiplaying out the bracket gives you a negative here, overall it works out as minus, had both brackets been positive though then it would be an addition.


When adding or subtracting different terms with differentiation, do them all seperately :)
 
SoSolid said:
ok thanks a lot, but shouldn't the power be -1/2 ?


No. You drop the power by one.

3/2 - 1 = 1/2


Fairly simple maths... can't do that then i dunno if you really want to be differentiating ;)

Integration for you soon my son :D
 
oops no my mistake, I gave a slightly different question on here to the one I was stuck on, such that you guys wouldn't be doing my homework for me. So that I could just get an idea of it. As you can tell, in my question it was to the power of 1/2, thus the differentiated form would be -1/2. My error.
 
SoSolid said:
oops no my mistake, I gave a slightly different question on here to the one I was stuck on, such that you guys wouldn't be doing my homework for me. So that I could just get an idea of it. As you can tell, in my question it was to the power of 1/2, thus the differentiated form would be -1/2. My error.


Yep that's right. But you see where my answer comes from right :p
 
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