Anyone know any Calculus?

Toggle sidebar Toggle sidebar
mrSHEiK124

mrSHEiK124

Lifer
Mar 6, 2004
11,488
2
0
Homework has a "Tuesday, March 1st" due date. Well, turns out there is no fucking Tuesday March 1st, and it's due in 3 hours. Halp.

1. Find lim(x->0) of [sin(a+2x) - 2sin(a+x) + sin(a)]/2

2. If y = (x/sqrt(a^2 - 1)) - (2/sqrt(a^2 - 1))arctan[sin(x)/(a+sqrt(a^2 - 1)+cosx)] show that dy/dx = 1 / (a+cosx)

3. Find y' if y = sin^2(cos(sqrt(sin(pi*x))))

Uh, I can barely understand what I wrote.
 
M

Matthiasa

Diamond Member
May 4, 2009
5,755
23
81
For The first just plug in 0 leaving it as what it is minus all the x terms. (has a really nice number that is gotten by simple inspection of the problem)
 
M

Matthiasa

Diamond Member
May 4, 2009
5,755
23
81
Why does edit creat new posts sometimes... Someone should fix that.
 
Last edited:
M

Matthiasa

Diamond Member
May 4, 2009
5,755
23
81
mrSHEiK124 said:
I typo'd then, it's all divided by x^2, not 2
Click to expand...


For that its still just plug in the numbers assuming a non zero a.

If a was zero however you could use l'hospital's rule.

I may be over thinking this though... It's been a while.
 
Last edited:
RedRooster

RedRooster

Diamond Member
Sep 14, 2000
6,596
0
76
Wow, I have been out of school for less than 10 years and have absolutely NO idea how you would go about solving that. I probably solved the same thing at some point too.
Never needed it once in my lifetime since though, don't let them tell you otherwise.
 
T

TheVrolok

Lifer
Dec 11, 2000
24,254
4,092
136
You know, I took 3 years of calc in high school and not a day since. I don't think I could even fumble my way through those problems now without the help of my trusty TI-89. I actually miss being able to do math. :(
 
ConstipatedVigilante

ConstipatedVigilante

Diamond Member
Feb 22, 2006
7,670
1
0
Chain rule/product rule/plug in numbers. I have a test on this stuff on 45 minutes - the hardest part is just not screwing up the algebra as you go through the problem.
 
DrPizza

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,601
167
111
www.slatebrookfarm.com
Assuming you've learned L'Hopital's rule, you need to apply it twice to the first problem.

2nd two are just straight up chain rule. 3rd is much easier than the 2nd.

No Ti-89? or Maple program?
Click to expand...
He's learning calculus - not calculatorus. If he can't do it without the calculator, then he knows nothing. Tis sad that some people associate being able to push the right buttons with knowing calculus.
 
Last edited:
mrSHEiK124

mrSHEiK124

Lifer
Mar 6, 2004
11,488
2
0
Augh. Not getting anywhere...

[sin(a+2x) - 2sin(a+x) + sin(a)]/x^2

sin(a) - 2sin(a) + sin(a) / 0

Can't divide by zero (ask 4chan)
 
M

Matthiasa

Diamond Member
May 4, 2009
5,755
23
81
DrPizza said:
Assuming you've learned L'Hopital's rule, you need to apply it twice to the first problem.
Click to expand...

The a means that if doing it by well his book, you probably shouldn't. :p
However that a makes no difference in the final answer so yeah.

mrSHEiK124 said:
Augh. Not getting anywhere...

[sin(a+2x) - 2sin(a+x) + sin(a)]/x^2

sin(a) - 2sin(a) + sin(a) / 0

Can't divide by zero (ask 4chan)
Click to expand...

Funny thing about that.. you can it just blows numbers to either positive or negative infinity at least when using limits.
 
Last edited:
M

Matthiasa

Diamond Member
May 4, 2009
5,755
23
81
mrSHEiK124 said:
Final answer being? I have to start driving, no time to listen to you guys argue...
Click to expand...

It goes to either +∞ or -∞ depending on what sin(a) is.


(can be shown by graphing)
Can also be show by the last term not having anything going to 0 in it.
 
Last edited:
You must log in or register to reply here.

TRENDING THREADS

COMPANY
RESOURCES
FOLLOW
Top Bottom