Finding the derivative of g(x)

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To find g'(0.1) for g(x) = f(3x), the chain rule is applied, resulting in g'(x) = 3*f'(3x). Substituting x = 0.1 gives g'(0.1) = 3*f'(0.3). Given f'(0.3) = 1.096, the final calculation yields g'(0.1) = 3.288. The discussion emphasizes the importance of using the chain rule in derivative calculations.
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Homework Statement



Let f(x) be a continuous and differentiable function on the interval 0 ≤ x ≤ 1, and let g(x)=f(3x). The table below gives values of f'(x), the derivative of f(x). What is the value of g'(0.1)?

http://img845.imageshack.us/img845/442/33806538.jpg

Homework Equations


The Attempt at a Solution



g(0.1) = f(3(0.1))
g(0.1) = f(0.3)
g'(0.1) = f'(0.3)
g'(0.1) = 1.096

Did I do the problem correctly? Thanks!
 
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Look correct assuming the picture and problems statement are what you have shown.
 
I think the answer should be E. g'(x) = 3*f'(3x). So, g'(0.1)=3*f'(0.3)=3*1.096=3.288
 
^ Actually that's correct because of the chain rule (haven't taken calculus in 5 years lol)

g(x) = f(u), where u = 3x so
g'(x) = f'(u)du = f'(3x)*3
 
shuohg said:
I think the answer should be E. g'(x) = 3*f'(3x). So, g'(0.1)=3*f'(0.3)=3*1.096=3.288

tazzzdo said:
^ Actually that's correct because of the chain rule (haven't taken calculus in 5 years lol)

g(x) = f(u), where u = 3x so
g'(x) = f'(u)du = f'(3x)*3



Thank you guys!
Forgot to use chain rule, thought I could just multiply 3*(0.3)
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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