Posted by **Matt** on Tuesday, March 2, 2010 at 9:38pm.

How do you take the derivation of the following function and equate to zero?

sqrt of (100t^2-320t+400).

- Calculus AB -
**Heather**, Tuesday, March 2, 2010 at 10:52pm
to take the derivative of an equation involving the square root it would be easier to set the whole equation in parenthesis and raise it to (1/2). you then bring the exponent down in front and decrease the by 1 to get (-1/2). this will make your equation in the denominator and times by (1/2). you then will have to take the derivative of the inside piece.

1/(2(sqrt(100t^2-320t+400))*(200t-320) which is the derivative of the inside piece)

and i'm guessing that by "equate" you mean set equal? sorry, i haven't heard many people say it that way. to do this just set the equation to zero and solve.

- Calculus -
**Reiny**, Tuesday, March 2, 2010 at 11:51pm
Heather's derivative is not correct ...

y = (100t^2-320t+400)^1/2

dy/dx = (1/2)(100t^2-320t+400)^(-1/2)(200t - 320)

= 0

(100t-160)/√(100t^2-320t+400) = 0

100t - 160 = 0

t = 160/100 = 8/5

etc

## Answer this Question

## Related Questions

- Calculus 2 (Differential Equation) - How would you solve the following problem ...
- CALCULUS. Check my answers, please! :) - The domain of f(x)=(1)/(sqrt(x^2-6x-7...
- Calculus - Could someone explain this question please. Suppose the population (...
- Pre Calculus - Find the roots of the function g(x)=x^3 +16x a)0,4i, -4i b)0,-4,-...
- calculus - A) How do you prove that if 0(<or=)x(<or=)10, then 0(<or=)...
- Calculus (please check my answer) - Find the Avrage value of the function i=15(1...
- Calculus - Please look at my work below: Solve the initial-value problem. y'' + ...
- ap calculus - Which of the following definite integrals gives the length of y = ...
- Calculus - A steady wind blows a kite due west. The kite's height above ground ...
- Calculus - Find the RMS value of the function i=15[1-e^(-1/2t)] from t=0 to t=4 ...

More Related Questions