# CALCULUS

posted by .

Use the product rule to calculate the derivative.
dh
dx
x = 4 ,

h (x) = (x^(-1/2) + 7x)(9 - x^-1)

very weird.. i know how to do it, i used product rule and got an answer in decimal but the website is not accepting it. Can any one help me?...

• CALCULUS -

Let's multiply it out and not use the product rule. The answer should be the same.

h(x) = 9x^(-1/2) -x^(-3/2) +63x -7
dh/dx = -(9/2)x^(-3/2) +(3/2)x^(-5/2) + 63

dh/dx @ x=4 = (-9/2)(1/8) +(3/2)(1/32)+63
= -9/16 +3/64 +63

## Similar Questions

1. ### Product Rule

Can someone please help me with this? f(x)=(x-2)^1/2 * (x^2-3)^3 find f'(x) using the product rul. This is what I came up with I just need to know if I did it right. f'(x)=(x-2)^1/2*3(x^2-3)+(x^2-3)^3*(1)^-1/2 Hopefully I did. Thanks.
2. ### Math, Calculus

Find the derivative of the function. y= xcosx - sinx What's the derivative?
3. ### Calculus/Derivatives

In addition, can you walk me through how to get the derivatives for these 2 statements, too?
4. ### Calculus again

Find the equation of the tangent to y=2-xe^x at the point where x=0 So I found the first derivative by doing the sum rule and product rule. I got e^(x)(x-1) Then I found the slope by substituting 0 for x and got -1. Then I found y …
5. ### Calculus

How do I use the chain rule to find the derivative of square root(1-x^2) also, are there any general hints or tips for determining when the chain rule and product or quotient rule should be used?
6. ### calculus

derivative of f(x)=arctan(x^2-x) is it the product rule or the chain rule?
7. ### Calculus

Use the Product Rule to find the derivative of the function. f(x) = (x^3 − 2x)(5x^2 + 2x)
8. ### Calculus

Use the product rule to find the derivative of the following. k(t)=(t^2-4)^2 k'(t)=
9. ### Calculus

Match the rule with the title: ____ 3. d/dx [f(x)/g(x) ]=(g(x) f^' (x)-f(x) g^' (x))/[g(x)]^2 ____ 4. d/dx [f(g(x))]=f^' (g(x))∙g'(x) ____ 5. d/dx [f(x)∙g(x)]= f(x) g^' (x)+g(x) f^' (x) ____ 6.d/dx [x]=1 ____ 7. d/dx [f(x)+g(x)]= …