Calculate the derivative of the function.
Using Chain Rule

r(x) = (0.1x^2-4.2x+9.5)^1.5

Question

Calculate the derivative of the function.
Using Chain Rule

r(x) = (0.1x^2-4.2x+9.5)^1.5

kropot72 · Answer

$$r \prime(x)=\frac{d(0.1x ^{2}-4.2x+9.5)^{1.5}}{d(0.1x ^{2}-4.2x+9.5)}\times \frac{d(0.1x ^{2}-4.2x+9.5)}{dx}$$

kropot72 · Answer

@chrislb22 Can you find the derivative of each of the terms on the right hand side?

anonymous · Answer

i think its 0.01-4.2

kropot72 · Answer

I think we must revise some differentiation first:
$$y=x ^{1.5}$$
$$\frac{dy}{dx}=?$$

anonymous · Answer

1.5

anonymous · Answer

hey what just happend?

kropot72 · Answer

$$y=x ^{1.5}$$
$$\frac{dy}{dx}=1.5x ^{(1.5-1)}=1.5x ^{0.5}=1.5\sqrt{x}$$
Do you follow?

anonymous · Answer

yes i do

kropot72 · Answer

Then you should be able to differentiate the first of the two terms on the right hand side of the equation in my first post above:
$$\frac{d(0.1x ^{2}-4.2x+9.5)^{1.5}}{d(0.1x ^{2}-4.2x+9.5)}=?$$

anonymous · Answer

im sorry im having a hard time figuring out what to do

anonymous · Answer

Let u = 0.1x² - 4.2x + 9.5
 -> u' = ...
     ( u^n ) '  = n u ^( n -1) * u'

zepdrix · Answer

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