What are the first and second derivatives of the function

In summary, the first and second derivatives of the function f(x)=(3-x)/(2x+5) can be found using either the quotient rule or the product rule. It is recommended to use the product rule, but both methods will result in the same answer. The correct derivatives are f'(x)= -11(2x+5)^-2 and f''(x)= 44(2x+5)^-3. There are various websites available where the function can be typed in and it will show all the maxima, minima, asymptotes, holes, and cusps.
  • #1
roy5995
29
0
What are the first and second derivatives of the function

f(x)=(3-x)/(2x+5)

How do i find them, do i use the quotient rule or do i change it to

f(x)=(3-x)*(2x+5)^-1 and use the product rule?
 
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  • #2
Personally I like the product rule better, but you get the same answer either way, so use whichever one you prefer.
 
  • #3
I think i got it

f'(x)= -11(2x+5)^-2
f''(x)= 44(2x+5)^-3

but does anyone know of a website where i can type in the function and it will show me all the max, mins, asymptotes, holes, cusps ...
 
  • #4
You made a mistake when you combined your terms in the first deriv., & therefore the 2nd is wrong too.
 
  • #6
How are roy's answers incorrect?

f'(x)= -11(2x+5)^-2
f''(x)= 44(2x+5)^-3

-11 times the quantity (2x+5) to the power of -2 is the correct answer as seen http://home.twmi.rr.com/faust9/calc problem.jpg

roy's answer could be written:

f'(x)= -11/(2x+5)^2
f''(x)= 44/(2x+5)^3

and it would be equivalent to what he has above.
 
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  • #7
Sorry those are not incorrect
 

FAQ: What are the first and second derivatives of the function

What is the definition of a derivative?

A derivative is a mathematical concept that represents the rate of change of a function at a specific point. In other words, it measures how much a function is changing at a given point.

What is the first derivative of a function?

The first derivative of a function is another function that represents the rate of change of the original function. It is denoted as f'(x) or dy/dx and can be interpreted as the slope of the tangent line at a specific point on the original function.

How is the first derivative calculated?

The first derivative of a function can be calculated using the limit definition of a derivative, which is the change in the function's value divided by the change in the independent variable as the change approaches zero. It can also be calculated using differentiation rules such as the power rule, product rule, or quotient rule.

What is the second derivative of a function?

The second derivative of a function is the derivative of the first derivative. It represents the rate of change of the rate of change of the original function. It is denoted as f''(x) or d²y/dx² and can be interpreted as the concavity of the original function at a specific point.

How is the second derivative calculated?

The second derivative of a function can be calculated by taking the derivative of the first derivative. In other words, it is the derivative of the derivative. It can also be calculated using differentiation rules such as the power rule, product rule, or quotient rule.

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