Given values, find derivatives

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Jacobpm64
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Given y = f(x) with f(1) = 4 and f'(1) = 3, find

(a) [tex]g'(1) if g(x) = \sqrt {f(x)}[/tex]
(b) [tex]h'(1) if h(x) = f(\sqrt {x})[/tex]

(a) [tex]g'(x) = \frac {1}{2} f(x)^\frac{-1}{2} * f'(x)[/tex]
[tex]g'(1) = \frac {1}{2} f(1)^\frac{-1}{2} * f'(1)[/tex]
[tex]g'(1) = \frac {1}{2}(4)^\frac{-1}{2} * 3[/tex]
[tex]g'(1) = \frac {3}{4}[/tex]

(b) [tex]h'(x) = f'(\sqrt{x})[/tex]
[tex]h'(1) = f'(\sqrt{1})[/tex]
[tex]h'(1) = f'(1)[/tex]
[tex]h'(1) = 3[/tex]

Are these correct?

I'm not sure if this was the correct approach.

Thanks.
 
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(a) correct(b) If [tex]h(x) = f(\sqrt{x})[/tex], then [tex]h'(x) = f'(\sqrt{x})\frac{1}{2}x^{-\frac{1}{2}}[/tex]. So it should be [tex]\frac{3}{2}[/tex]
 
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thanks, just a simple mistake :redface: