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anonymous
 5 years ago
y'' for y= (x^2+9)^4
anonymous
 5 years ago
y'' for y= (x^2+9)^4

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Take the first derivative using the chain rule and then take the derivative of that.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Second derivative will require both the chain rule and the product rule.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0could you show me it worked step by step

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[y'=4(x^2+9)^3(2x)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0That's the first derivative. Do you see where things might have come from?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes i had it all right except the 2x and thats by taking the derivative of the things inside the brackets

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes :) that is the chain rule.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So now we move on to the second derivative which involves the product rule.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Do you know how to use the product rule?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay i got.... 4(x^2+9)^3 (2) + (2x) 12(x^2+9)^2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Very close. First half is correct. Second half you forgot something.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0oh do the product rule to finish?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the books has 8(x^2+9)^3 + 48x^2(x^2+9)^2 = 8(x^2+9)^2(7x^2+9)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well the book is correct lol. All you forgot in your was the chain rule on the second half. Should have been (2x)12(x^2+9)(2x) that 2x on the end is what you forgot.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0why is the 2x at the end as well?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok so when you did the second half of the product rule you can say to yourself (2x) times the derivative of the function. Well the derivative of that function 4(x^2+9)^3 is 12(x^2+9)^(2) times the chain rule (2x).

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay so now where do they get their answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0got the first part, but didnt get it after the simplifying

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0They probably multiplied stuff out and then it eventually got them to that answer. Truthfully, I have never seen a teacher who would not accept the first answer you have. The other answer is just tedious work.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Actually I just looked at their second answer and you could factor...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay could you help me with a ln y''?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay. I am horrible at ln problems but here is the original y'' for y= ln x/x^2

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok this is a quotient rule problem or can be a product rule if you rearrange it. Take your pick.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0SO IT COULD BE (LN X)(X^2)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well could be lnx(x^2). Normally a lot of people prefer to use the product rule when possible, but it's a little easier.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The derivative of lnx is 1/x

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay so y' is lnx(2x^3) + (x^2)(1/x)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0okay now im going to need some help..lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0no just straight so i can see what to do

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm confused. So what do you need help on? Sorry lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ah. Ok. Well you can use the product rule again for the second derivative, but twice. So use the product rule for the lnx(2x^3) and then add that with the result of the product rule of (x^2)(x^1). I rewrote 1/x so it's easier to see.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0can you show me it worked out?
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