Calculus
posted by Michelle .
Using the derivative definition of f ‘ (x) = (f (x+h) – f (x)) / (h) find the derivatives of the following…
1. f(x) = (2x1) / (x+2)
2. f(x) = sqrt (3x1)
3. f(x) = 3x^4
my answers were:
1. –x+3
2. (3) / [2(sqrt(3x1))]
3. 12x^3
are my answers right?

for the first one, I got 5/(x+2)^2
the other two are correct
Respond to this Question
Similar Questions

Calculus
show that the curves r=asin(è) and r=acos(è) intersect at right angles. can you show that the derivatives for each are the negative reciprocal of each other? 
Calculus derivatives
f(a) = a + √a (a) Find the derivative of the function using the definition of derivative. 
Calculus  derivatives
Okay, I want to find the derivative of (x^x)^(x^x)... Well, I already went through the process of finding the derivative of just x^x (I used ln to do this). This is what I found... dy/dx = x^x(lnx+1) So now I want to find the derivative … 
Calculus 1
Could you please explain how to find the slope using the definition of derivative of the function y=2*sqrt(x) 
math
find derivative using limit definition: f(x) = x  sqrt(x) so f'(x) = lim h>0 [f(x+h)  f(x)]/h but I keep trying to solve by multiplying by the conjugate but I can't figure it out..there's nothing that can be cancelled or anything … 
calculus
sqrt(x^2  9) / x I need to solve this using the definition of a derivative [f(a+h)  f(a)]/h I can't seem to get it :\ 
Maths Calculus Derivatives & Limits
Using the definition of the derivative evaluate the following limits 1) Lim h> 0 [ ( 8 + h )^1/3  2 ] / h 2) Lim x > pi/3 ( 2cosx  1 ) / ( 3x  pi) 
Calculus (Derivatives)
Using the product rule, find the derivative of the following function: (x^1/2 cscx sinx). 
science
find derivative of f(x)=1/sqx^2+1 by using the definition of derivatives 
calculus
Find the derivative of the function using the definition of derivative. g(t)= 9/sqrt(t) g'(t)= state the domain of the function and the domain of the derivative (use interval notation)