Assuming :
This is very close to the derivative posted above. What is the derivative of ?
Hi,
I am solving a problem which involves calculating the surface are of a solid revolution about the x – axis. I have found that the surface area can be given by:
I have done this using the trapezium rule as I know the values of r and d, so I have a rough estimate of a figure I am aiming for.
The question I am trying to answer says to use the standard integral:
I am struggling to interpret the r+rd/√(r^2-x^2) into the form dx/√(k^2-x^2) in order to evaluate the integral. Any help or guidance would be appreciated as I have spent too much time trying to do this.
Thanks
Hello, freethinker!
I am solving a problem which involves calculating the surface area of a solid revolution about the x–axis.
I have found that the surface area can be given by: .
I have done this using the trapezium rule as I know the values of r and d,
so I have a rough estimate of a figure I am aiming for.
The question says to use the standard integral: .
. . This is NOT a standard formula!
I am struggling to interpret the into the form in order to evaluate the integral.
. . Really? . . . What's stopping you?
Any help or guidance would be appreciated as I have spent too much time trying to do this. Thanks.
That "standard integral" would be: .
We have: .
Now finish it . . .