https://gyazo.com/bdf72a48e0fea9034530671466b06567

Question

jamaljunior · Answer

please someone help with this

mathmale · Answer

Please post the original question.  Otherwise you're not giving us enough info with which to help you.

jamaljunior · Answer

he went offline @mathmale http://openstudy.com/users/jamaljunior#/updates/58409138e4b071fda87fc9ab

amorfide · Answer

nvm i rewrite I made a mistake

mathmale · Answer

Jamal:  It is confusing when you have 2 or more questions posted at the same time.  Please post ONLY ONE at a time.  Thank you.

mathmale · Answer

I have responded to your other question.  You need to inform me and amorfide which question you want to discuss first.

jamaljunior · Answer

is the answer B?

125/2 = 62.5

amorfide · Answer

$$y=250(0.5)^{x}$$
take the natural log of both sides

$$lny=\ln(250(0.5)^{x})$$

|dw:1480637680569:dw|

$$lny=\ln(250)+\ln(0.5^{x})$$

|dw:1480637734995:dw|


$$lny=\ln(250)+x\ln(0.5)$$

differentiate with respect to x

$$\frac{ 1 }{ y }\frac{ dy }{ dx }=0+\ln(0.5)$$
multiply by y on both sides

$$\frac{ dy }{ dx }=yln(0.5)$$

we know that
$$y=250(0.5)^{x}$$

$$\frac{ dy }{ dx }= (250(0.5)^{x})\ln(0.5)$$

dy/dx is the differential which is the rate of change

you want the change from x=2, to x=0
so let x=2
let x=0

subtract the answers

f'(2)-f'(0) as you were previously told