Thread: Simple Differentiation help

i need to differentiate these 3 functions.
for a, am i supposed to use the quotient rule ? or would it just be 3x^2/1?
x by itself is equal to 1 right?
and constants are mostly ignored except for special situations?


Any help is appreciated, as i'm just learning how to do this and i don't have a textbook..



a) x^3+2 / x-5


3x^2(x-5) – 1 (x^3+2)/(x-5)^2

b) (2x^4 + x)(-4x^2 + 1)
c) Find dy/dx if y=2u^3 – 5u , u=x^3+2

Originally Posted by seanP

i need to differentiate these 3 functions.
for a, am i supposed to use the quotient rule ? or would it just be 3x^2/1?
x by itself is equal to 1 right?
and constants are mostly ignored except for special situations?


Any help is appreciated, as i'm just learning how to do this and i don't have a textbook..



a) x^3+2 / x-5


3x^2(x-5) – 1 (x^3+2)/(x-5)^2

b) (2x^4 + x)(-4x^2 + 1)
c) Find dy/dx if y=2u^3 – 5u , u=x^3+2

Yes, for the first one we have:



And use the quotient rule to get:



For the third one we have (by substituting the u in):



By using the chain rule on the exponents we get the following:



I figured you could figure out the second problem by these examples, but if you still want some help post here and I'll help some more

thanks for clearing that up