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Thanks

Thank you so much for the help thickhead,it solved my problem ,but one thing u said, I cant figure it out is that if

is expressed in terms of , I guess in this problem its not possible for x = 0.Thanks

But again I didnt understood the last three steps so I didn't change it . It is what written in my book.

**debjit625**- Replies: 6

Find the value of

for ,when .In the my book its already solved the problem is that I don't understand after a certain point ,the steps.

After solving we have

Putting x = 0

Replacing n by n-2,we get similarly

After this point /step I don't understand anymore ,here is the rest which I want you people to explain me how and why its done (which is actually my question) ...

Also

(the first and second derivative at 0 )Thus

,if n is evenand

,if n is oddThanks

Here is a link please read it https://www.physicsforums.com/threads/s … ic.873144/

Thanks

**debjit625**- Replies: 6

This property is given in my book.

The square of any determinant is a symmetric determinant.

Well it works when I take a determinant say 3x3 and multiply it by itself using row to row multiplication.

But it fails if I multiply using row to column.

Thanks

Thanks

OK I got that (It should be the case), but I want to know if that is a vector rule? if yes can you give me a resource where I can understand why its like that and more.

zetafunc Thanks

**debjit625**- Replies: 4

Hi I got a problem

Let a and b be two vectors...

(a x b) = |a| |b| sin(t) n

where t is the angle between the two vectors a and b ,and n is the unit vector in the direction as per right hand rule.

If I square the equation

(a x b)^2 = |a|^2 |b|^2 (sin(t))^2 n^2

(a x b)^2 = |a|^2 |b|^2 (sin(t))^2

Now if I take the square root of both the sides

(a x b) = |a| |b| sin(t) ...which is the problem LHS is vector and RHS is scaler

I think there is some rules for vectors which I didn't follow may be... but what please explain and give me some reference where I can read more about this.

Thanks

Thanks

**debjit625**- Replies: 2

Well I solved this in two ways ,one of them is wrong or what I dont know

First answer is

Which is correct as many book have them

But if I try to put 1 = tan(pi/4) and then try to solve it I get something else

I am not able to understand it ,can anybody explain me where I am wrong.....

Thanks

Well I did it like this

By equation of the sphere its already given that the sphere is at origin (0,0,0).

Now from there we get radius of the sphere is

Now we have to find the distance 'd' of the plane from origin and that will be

Now use Pythagoras theorem to find the radius of the section by the plane

Good Luck

Thanks Bob

**debjit625**- Replies: 7

Find the radius of the circular section of sphere

by the planeMy answer came out to

Did I did it correctly,I am bit confused over the question.

Thanks

Hi bob

When I solve the equation

as my answer isAnd when I solve the equation

as my answer is or .Now which one is correct ,are both correct?

Now putting the different values for "n" we can get the value for theta and put it in the equation and check,but I did just a couple and I know if I can graph it it will show but which application to use for this kind of job I dont know.

Thanks

**debjit625**- Replies: 3

Hi

I know that

1) The general solution for

is

And

2) The general solution for

is

Now my question is, in an equation like

,which way should I select i.e.. its in both the forms

and

in that case we rewrite the equation

Thanks

Yes stefy I agree with you, but still we use approx symbol for that... don't we ?,in the book they directly used equal symbol.

Bob the topic was about... calculating vectors...

Their are two force vectors given,first one 70N north and another is 50N south west,so calculate the resulting force and direction.

Well,I thought that but in that case physics books use

approx symbol in general.So I am right with the math ?

**debjit625**- Replies: 6

Hi,

In a physic book I found this

Is the math correct ? as far my math goes it should be 1.02

Thanks

Yes dude it make sense now ,I tried to solve and after coming to this point I gave up

Thanks anonimnystefy and Bob for the help...

And thanks Bob and anonimnystefy for the reply

Sorry for late reply...

Here is how I did

The answer in the book is sin(a + b) = 24/25 as bob got 0.96,@Bob but I didn't understood what you did... can you explain and why my equation is not working

**debjit625**- Replies: 11

Hi, guys

I tried but I can't solve it...

If a,b are two different values of x lying between 0 and 2 pi (i.e.. 0 to 360 degrees) which satisfy the equation 6 cos x + 8 sin x = 9 ,find the value of sin(a + b).

Well what I did was I turned that equation into an quadratic equation and find the roots and also use the relation of the sum of the roots.But no luck my solution is getting no where....

here is what I got when I turned it into an quadratic...

Thanks

I will purchase a laptop (Dell Inspiron 14R) with it installed.The over all cost seems ok.

Nvidia GeForce GT 730 M is designed for laptops/notebooks,for desktop their are other series both from AMD and Nvidia like Nvidia GTX series is best on desktop platform ,for future I am planning to buy a graphic card from GTX series for my desktop.