Question

determine f^(2)(x) when f(x)=3sinx+cosx

Answer 1

are you trying to find the second derivative?

Answer 2

i guess so

Answer 3

f'(x) = the derivative of 3sin(x) + the derivative of cos(x), can you do that?

Answer 4

no i can not

Answer 5

ok no problem, the derivative of sinx is cosx, you just need to remember that, and the derivative of 3 times sinx is just 3 times cosx, so the constant 3 just goes with it. The derivative of cosx is -sinx, again you just need to remember that, so the derivative of the whole thing is those two derivatives added together

Answer 6

\[f'(x) = 3\cos(x) - \sin(x)\]

Answer 7

but this is just the first derivative. To find the second derivative you repeat the process I explained above

Answer 8

thanks so much!