
Please post any and all homework or other textbookstyle problems in one of the Homework & Coursework Questions...

Feb2313 09:24 AM
micromass

1 
44,915 
Hi!
question: Two sides of a triangle are formed by vectors i  4jk and 2i  j+k. The area is ?
A=1/2bh so I...

Sep2203 08:03 AM
HallsofIvy

2 
6,176 
The vector 2 + j2 is the same as what?
I know that j2 is 1 so the answer would be 2 for the magnitude but what...

Sep2103 09:04 PM
HallsofIvy

6 
2,538 
Hi!
The quantity (absolute value vectorA x vectorB close absolute value)^2 + (absolute value vectorA * vectorB close...

Sep2103 08:57 PM
HallsofIvy

5 
7,749 
on a ti83 calculator, how do you put in cubic roots?

Sep2403 01:36 PM
StephenPrivitera

2 
2,626 
Please help with Antiderivitives! Need explanation and how to use them. Thank you

Oct603 05:24 AM
phoenixthoth

5 
4,628 
This comes from quantum mechanics but it's basically a Fourier integral I can't quite do...
F(k) = 1/sqrt(2a*) * ...

Sep2803 02:15 PM
mmwave

2 
3,817 
Has anyone ever seen this? It's an interactive online textbook in analysis in a single real variable. As an...

Oct703 04:45 PM
Tom Mattson

7 
2,889 
Here's what I got to prove where '.' is dot.
A.B=A.C Then B=C True or false? If true, prove it in general terms,...

Oct503 03:51 PM
HallsofIvy

6 
11,740 
I'm now teaching myself several topics on definite integrals for a math test on monday. Here are a few problems that I...

Oct1003 05:31 PM
KLscilevothma

8 
3,271 
i was stumbled on a problem was i was looking over my book...i can do things like, differntial geometry, fourier...

Oct603 05:12 AM
phoenixthoth

5 
3,488 
Greeting
A TA has got me very and utterly confused. He won't be avaible for a few days, so I'm asking you guys.
...

Oct803 04:21 PM
Kalimaa23

2 
2,249 
hi.
how can I prove that if A is a converges and B diverges
that the Sum of these series (A +B) diverges..
...

Oct803 06:57 AM
HallsofIvy

5 
2,370 
out of curiousity, when do "most" people do calculus? when do they start?

Oct503 10:24 PM
Kalimaa23

2 
2,429 
I am trying to use Excel to calculate fast fourrier equation/data into graph without success. Would be grateful of...

Oct703 09:16 AM
Charlie50

0 
4,137 
Can anyone please show me how to prove the problem below using epsilons and deltas. Thanks a lot...I'm so stuck...
I...

Oct903 11:17 AM
Soroban

5 
3,733 
Hi There,
I have this Simple Question In Limits :
If limx>3 (f(x)  2) / (x  3) = 7
Then limx>3 (x2f(x)  18)...

Oct1003 03:05 AM
Zargawee

5 
4,927 
Hello! I have a math problem (mostly proofs) that im stuck
on, partially because I do not know where to begin and...

Oct803 06:51 AM
HallsofIvy

2 
2,465 
y = x tan x
y' = tan x + x*sec^2(x)
y'' = sec^2(x) + d/dx (x*sec^2(x))
= ... + (d/dx(sec^2(x)) +...

Oct1003 11:47 PM
PrudensOptimus

3 
6,120 
Someone plz show me how to do the problem below, thanks very much.
1)***Use the known area of a circle to find the...

Oct1203 10:55 AM
HallsofIvy

7 
2,429 
The curves r1(t)=<t,t^2,t^3> and r2(t)=<sin t, sin 2t, t> intersect at the origin. Find their angle (acute) of...

Oct1003 12:22 PM
Juntao

4 
2,282 
Can someone plz show me how to show that this problem below is CORRECT? Thanks a lot.
Integral of dx/(1x^2) = x/(1x)

Oct903 11:04 PM
Hurkyl

3 
2,535 
This equation of a sphere in spherical coordinate form:
ρ = 4sinφcosθ converts very readily to (x2)2 +...

Oct1003 10:18 AM
selfAdjoint

3 
2,870 
Plz help me do the problem below. thanks a lot.
Show that the following integral is CORRECT:
Indefinite Integral of...

Oct1203 12:24 PM
gigi9

3 
2,240 
Take the integral of:
sin3x, with respect to x.  interval
I end up getting 0/3:
=
= /3

Oct1203 12:44 AM
Suicidal

1 
6,398 
Here's the problem. Find the gradient of f(x,y). f(x,y)=(x^2)e^2y.
I don't have the solution to this and I need...

Oct1203 11:53 PM
StephenPrivitera

3 
2,172 
1)Find equations of both lines through point (2,3) that are tangent to the parabola y=x^2+x.
2)The normal line to...

Oct1303 06:28 AM
HallsofIvy

3 
3,158 
Hello ,
I need some help with this, I can't find a way to solve it :
limx>0 (1/tan x)2  1/x2
from it's graph ,...

Oct2103 09:06 AM
Zargawee

9 
1,922 
I am excited to say, that just today I have discovered a new notation for triple intergrals! Currently I am working...

Oct1503 08:33 AM
MathematicalPhysicist

5 
1,989 
I try to take the integral of sqrt(4x1) with respect to x...
The correct answer is sqrt((4x1)^3)/6, but I...

Oct2203 02:38 PM
lavalamp

9 
4,197 
OK, say a 90deg triangle, with 5, 12, 13.
We know area of it is 30.
because 1/2bh... now how do u express it...

Oct1703 08:24 AM
HallsofIvy

16 
15,534 
Considering the problem of finding the area under a parametric curve, I thought,
y=y(t), x=x(t)
A=ydx=yx'(t)dt...

Oct1803 09:23 AM
HallsofIvy

1 
2,169 
Can someone plz help me to figure out how to do these problems below?...Or at least get me started in the right...

Oct2003 10:00 PM
gigi9

2 
2,217 
There is a question which is as follows:
(4^x)/(ln4)
I have tried many times to get the answer but with no...

Oct2003 05:32 AM
renedox

3 
6,039 
How do you find the integral of a product, say x*sqrt(1+x) dx...
I am very confuzed with all the notation is...

Oct2103 05:46 AM
HallsofIvy

7 
29,035 
Plz help me out w/ the problem below. Thanks.
Find the length of the specified arc of the given curve:...

Oct2103 04:12 AM
KLscilevothma

1 
1,705 
Plz explain to me what the problem below is talking about? I don't really understand what it's saying...I can't...

Oct2203 01:58 PM
HallsofIvy

4 
1,576 
All right, I know that partial derv. are not all that hard. All you do in lets say f(x)= x^2+2yx+3y is find the...

Oct2403 10:03 AM
Arden1528

4 
1,708 
limn>oo(x2n1)/(x2n+1)
I can't figure this one out. I've tried everything. I tried splitting the fraction into...

Oct2403 07:10 AM
HallsofIvy

4 
1,593 
Someone plz help me to do this problem below. Thanks
1)a) Verify that y= e^(x) and y= e^(2x)are both solutions of...

Oct2603 03:02 PM
HallsofIvy

1 
1,317 
) IF the rate of increase o f population of a country is 3 percent every year, by what factor does it increase every...

Oct2603 02:55 PM
HallsofIvy

1 
1,247 