4th derivative of f(x) = (2 + 3x)^4

[Math wiz ya rite 09]

If f(x) = (2+3x)^4

then the 4th derivative of f is?

 

[Math wiz ya rite 09]

answer??

is the answer

4!(2+3x)

 

[skeeter]

almost ... you're forgetting the chain rule.

 

[Math wiz ya rite 09]

would it be??

4!(3)

 

[skeeter]

no

 

[Math wiz ya rite 09]

ok I am missing something... please explain.

if it's not 0, then im lost.

 

[skeeter]

f(x) = (2+3x)⁴

f'(x) = 4(2+3x)³ * 3

f''(x) = 4*3(2+3x)² *3²

f'''(x) = 4*3*2(2+3x)*3³

f⁴(x) = 4! * 3⁴

 

[Math wiz ya rite 09]

thanks. i will remember the chain rule.