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System Message

[00:00:00] *** Please note: All sessions are recorded for quality control. ***

Tiffany (Customer)

[00:00:00] help with problem

Gilberto E (Tutor)

[00:00:11] Hi

Tiffany (Customer)

[00:00:23] i need help evaluating an
integral using the
fumdemental theorem

Gilberto E (Tutor)

[00:00:37] Ok. Let's see it

Tiffany (Customer)

[00:02:13] that's it

Gilberto E (Tutor)

[00:02:31] Ok. How have you tried to approach this problem
?

Tiffany (Customer)

[00:03:34] I have no clue how to solve it.

Gilberto E (Tutor)

[00:03:56] That's ok. One sec..

[00:04:59] Ok. How about we try a u substitution?

Tiffany (Customer)

[00:05:16] ok

Gilberto E (Tutor)

[00:05:39] what will be du?

Tiffany (Customer)

[00:06:36] i am not sure

Gilberto E (Tutor)

[00:07:06] What's the derivative of secx?

Tiffany (Customer)

[00:07:30] secxtanx

Gilberto E (Tutor)

[00:07:45] Good

[00:08:34] and what will be our new bounds?

Tiffany (Customer)

[00:09:16] i am not sure

Gilberto E (Tutor)

[00:09:36] Do you know how to solve for the new bounds
?

Tiffany (Customer)

[00:10:27] no.

Gilberto E (Tutor)

[00:10:43] That's ok. You will learn today

[00:11:04] Simply, let's plug each of our bounds into secx to get them in terms of u.

[00:11:34] what is sec(pi/3)?

Tiffany (Customer)

[00:12:41] 2

Gilberto E (Tutor)

[00:12:48] Good

[00:12:55] and sec(0)?

Tiffany (Customer)

[00:13:13] 0

Gilberto E (Tutor)

[00:13:25] Are you sure?

Tiffany (Customer)

[00:13:44] 1

Gilberto E (Tutor)

[00:13:50] Good

[00:14:09] Ok. So we got everything set. Now what's next?

Tiffany (Customer)

[00:14:48] not sure

Gilberto E (Tutor)

[00:15:05] Well, what's the integral of 4?

Tiffany (Customer)

[00:15:33] 4x

Gilberto E (Tutor)

[00:15:42] 4u

[00:15:59] what's next?

Tiffany (Customer)

[00:16:53] do we substitute 2 for u

Gilberto E (Tutor)

[00:17:02] yes

Tiffany (Customer)

[00:18:14] 8-4 = 4 ?

Gilberto E (Tutor)

[00:18:26] Awesome!

Tiffany (Customer)

[00:19:04] is that the final answer?

Gilberto E (Tutor)

[00:19:13] Yes

Tiffany (Customer)

[00:19:23] can you explain again how we
set up the new bounds?

Gilberto E (Tutor)

[00:19:32] Sure.

[00:19:50] We simply take our original bounds, and plug them in for whatever we let u equal.

[00:20:30] whatever the answers are, we choose as our bounds

Tiffany (Customer)

[00:20:54] ok

[00:20:57] thank you

Gilberto E (Tutor)

[00:21:01]

[00:21:05] No problem.

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