J Jason76 Senior Member Joined Oct 19, 2012 Messages 1,180 Sep 30, 2013 #1 \(\displaystyle f(x) = \sqrt{3} x + \sqrt{2x}\) \(\displaystyle f(x) = (3)^{1/2} x + (2x)^{1/2}\) \(\displaystyle f'(x) = ? + \dfrac{1}{2}(2x)^{-1/2}\) \(\displaystyle f'(x) = ? + x^{-1/2}\)
\(\displaystyle f(x) = \sqrt{3} x + \sqrt{2x}\) \(\displaystyle f(x) = (3)^{1/2} x + (2x)^{1/2}\) \(\displaystyle f'(x) = ? + \dfrac{1}{2}(2x)^{-1/2}\) \(\displaystyle f'(x) = ? + x^{-1/2}\)
D Deleted member 4993 Guest Sep 30, 2013 #2 Jason76 said: \(\displaystyle f(x) = \sqrt{3} x + \sqrt{2x}\) \(\displaystyle f(x) = (3)^{1/2} x + (2x)^{1/2}\) \(\displaystyle f'(x) = ? + \dfrac{1}{2}(2x)^{-1/2}\) \(\displaystyle f'(x) = ? + x^{-1/2}\) Click to expand... \(\displaystyle \frac {d}{dx}[C*x] \ = \ C \)
Jason76 said: \(\displaystyle f(x) = \sqrt{3} x + \sqrt{2x}\) \(\displaystyle f(x) = (3)^{1/2} x + (2x)^{1/2}\) \(\displaystyle f'(x) = ? + \dfrac{1}{2}(2x)^{-1/2}\) \(\displaystyle f'(x) = ? + x^{-1/2}\) Click to expand... \(\displaystyle \frac {d}{dx}[C*x] \ = \ C \)
J Jason76 Senior Member Joined Oct 19, 2012 Messages 1,180 Oct 1, 2013 #3 Since, at this point, were not supposed to know the chain rule, then this was how it's supposed to come out: \(\displaystyle f(x) = \sqrt{3} x + \sqrt{2x}\) \(\displaystyle f(x) = \sqrt{3} * x + \sqrt{2} * \sqrt{x}\) \(\displaystyle f(x) = \sqrt{3} * x + \sqrt{2} * x^{1/2}\) \(\displaystyle f'(x) = \sqrt{3} * 1 + \sqrt{2} * \dfrac{1}{2}x^{-1/2}\) Answer
Since, at this point, were not supposed to know the chain rule, then this was how it's supposed to come out: \(\displaystyle f(x) = \sqrt{3} x + \sqrt{2x}\) \(\displaystyle f(x) = \sqrt{3} * x + \sqrt{2} * \sqrt{x}\) \(\displaystyle f(x) = \sqrt{3} * x + \sqrt{2} * x^{1/2}\) \(\displaystyle f'(x) = \sqrt{3} * 1 + \sqrt{2} * \dfrac{1}{2}x^{-1/2}\) Answer