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anonymous
 5 years ago
If f (x) = 4sin(x)+3(x^x), find f'(2).
anonymous
 5 years ago
If f (x) = 4sin(x)+3(x^x), find f'(2).

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Find the derivative of f'(x) and then plug 2 into it.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i have difficulty on finding the f'(x)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The challenge is 3x^x. (1) Set y=3x^x. (2) ln y=xln3x. (3)Solve this as implicit differentiation with the left side giving you derivative of y and chain rule dy/dx. Solve for dy/dx. Move y quantity to right side of eq. Plug in value of y from (1). I am being evasive so you work it out yourself.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0y=3x^x lny=xln3x y'/y=1*ln3x+(3/3x)*x y'=(ln3x+1)3x^x is that it?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Good job. I think you got it.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but i still got a wrong answer...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Show us what you got. Some times answers written in different forms meaning the same thing. Master's students write these answer things; they have no sense of humor.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0f'(x)=4(cosx)+(ln3x+1)*3x^x f'(2)=4(cos2)+(ln6+1)*12 correct answer was 18.6531788205308

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The derivative is going to be f'(x) = 4cos(x) + 3x^x(1+ln(x))...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0counld you show me how to get this part (1+ln(x))? coz i got this part wrong and i didnt know how to do this. thanks!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0y=3x^x ln(y) = ln(3x^x) * Note where you made a mistake, you can't drop the ^x in front of the log until you take care of the three in front of it, first. ln(y) = ln(3) + ln(x^x) ln(y) = ln(3) x + xln(x) Differentiate... y / y' = ln x + 1 y = 3x^x (lnx + 1)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Sorry, ln(y) = ln(3) x + xln(x)... Should be... ln(y) = ln(3) + xln(x)...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i see! so we need to apply the product rule too when we take the ln?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yeah, because you have a function of x (just x itself) times another function of x (being ln x)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0As far as I can tell you got the calculus right. The number is off two units one way or another. Calculators are very specific and it easy to send wrong info when calculating ln and cos. I think your teacher would give you credit. Then important lesson here is learning how to manipulate the variable when it is in the exponent.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The process was correct, but he needs to make sure he's using the logarithm rules correctly... ln(a*b^x) != x ln(a * b). Need to split it into ln a + ln (b^x) first.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how about differntiating x^x?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i thought its (x^x) (lnx)?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You would get the same thing, except for where you multiple x back in, at the end.. Think about it. All the step did where you split the log from ln (ax^x) into ln a + ln(x^x) was produce a constant which disappears in the differentiation. The only part that would produce something with the a in it, would be where you multiple each side by y, to isolate y' in the last step...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yeah, a possible mistake. In step (2) try is 3xlnx.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0multiply y back in* tired
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