How do I find dy of (x+1)^(2/3) ? And then when x=-2 and dx=.0002 ?
A Angela123 Junior Member Joined Oct 9, 2008 Messages 54 Jul 14, 2009 #1 How do I find dy of (x+1)^(2/3) ? And then when x=-2 and dx=.0002 ?
D Deleted member 4993 Guest Jul 14, 2009 #2 Angela123 said: How do I find dy of (x+1)^(2/3) ? And then when x=-2 and dx=.0002 ? Click to expand... Please post the COMPLETE and EXACT problem. I assume you re given, y = (x+1)[sup:292cpalh]2/3[/sup:292cpalh] and you need to find ?y at x = -2 and ?x = 0.0002 We know ?y = f(x+?x) - f(x) Please show us your work indicating exactly where you are stuck - so that we know where to begin to help you.
Angela123 said: How do I find dy of (x+1)^(2/3) ? And then when x=-2 and dx=.0002 ? Click to expand... Please post the COMPLETE and EXACT problem. I assume you re given, y = (x+1)[sup:292cpalh]2/3[/sup:292cpalh] and you need to find ?y at x = -2 and ?x = 0.0002 We know ?y = f(x+?x) - f(x) Please show us your work indicating exactly where you are stuck - so that we know where to begin to help you.
B BigGlenntheHeavy Senior Member Joined Mar 8, 2009 Messages 1,577 Jul 14, 2009 #3 y = f(x) = (x+1)2/3\displaystyle y \ = \ f(x ) \ = \ (x+1)^{2/3}y = f(x) = (x+1)2/3 y′ = f′(x) = dydx = 23(x+1)−1/3 = 23(x+1)1/3.\displaystyle y' \ = \ f'(x ) \ = \ \frac{dy}{dx} \ = \ \frac{2}{3}(x+1)^{-1/3} \ = \ \frac{2}{3(x+1)^{1/3}}.y′ = f′(x) = dxdy = 32(x+1)−1/3 = 3(x+1)1/32. Hence dy = 2dx3(x+1)1/3\displaystyle Hence \ dy \ = \ \frac{2dx}{3(x+1)^{1/3}}Hence dy = 3(x+1)1/32dx Now plug in your values, and you′re done.\displaystyle Now \ plug \ in \ your \ values, \ and \ you're \ done.Now plug in your values, and you′re done.
y = f(x) = (x+1)2/3\displaystyle y \ = \ f(x ) \ = \ (x+1)^{2/3}y = f(x) = (x+1)2/3 y′ = f′(x) = dydx = 23(x+1)−1/3 = 23(x+1)1/3.\displaystyle y' \ = \ f'(x ) \ = \ \frac{dy}{dx} \ = \ \frac{2}{3}(x+1)^{-1/3} \ = \ \frac{2}{3(x+1)^{1/3}}.y′ = f′(x) = dxdy = 32(x+1)−1/3 = 3(x+1)1/32. Hence dy = 2dx3(x+1)1/3\displaystyle Hence \ dy \ = \ \frac{2dx}{3(x+1)^{1/3}}Hence dy = 3(x+1)1/32dx Now plug in your values, and you′re done.\displaystyle Now \ plug \ in \ your \ values, \ and \ you're \ done.Now plug in your values, and you′re done.
A Angela123 Junior Member Joined Oct 9, 2008 Messages 54 Jul 14, 2009 #4 I messed up. The whole problem is: ((x+1)^(2/3))-3 when x=-2 and dx=.0002
D Deleted member 4993 Guest Jul 14, 2009 #5 Angela123 said: I messed up. The whole problem is: ((x+1)^(2/3))-3 when x=-2 and dx=.0002 Click to expand... Follow the same process....
Angela123 said: I messed up. The whole problem is: ((x+1)^(2/3))-3 when x=-2 and dx=.0002 Click to expand... Follow the same process....