Integrals and Derivatives: Solving Problems with Limits and Rates of Change

SA32
Messages
31
Reaction score
0

Homework Statement


In the attachment: 5aef, 6abc


The Attempt at a Solution


5a.) I started by dividing the question into two integrals: the integral of 2sin(x) evaluated from 0 to pi/4 minus the integral of 4sec2(x) evaluated from 0 to pi/4. Then the anti-derivative of 2sin(x) is -2cos(x) and the anti-derivative of 4sec2(x) is 4tan(x). I'm not sure if this is correct, though?

5e&f.) I'm not even sure what this is asking. It looks like "the integral of the derivative", which, according to my notes, is f(x)+C, but... help? I'm not sure.

6abc.) Again, not sure what this is asking. Looks like the derivative of the integral, which is f(x) in my notes. I made an attempt at the first one using the way my friend said to do it, you can see it in the second attachment, but I don't know if it is correct.

Thanks for any help!
 

Attachments

  • calcu.JPG
    calcu.JPG
    25.4 KB · Views: 424
  • 6acalc.JPG
    6acalc.JPG
    4.8 KB · Views: 471
Physics news on Phys.org
Yes, 5e and 5f are asking for the integral of a derivative, and 6 is asking for the derivative of an integral.
 
For 5a) what you're thinking is right so keep doing it.

For 5e) or 5f) use that

\int_{a}^{b} \frac{df}{dx}{}dx= f(b)-f(a)

For 6abc) use the Leibniz-Newton formula and the chain rule of differentiation.

Daniel.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
Back
Top