Recent content by okh

Thank you. Yeah, that may be the reason.

Homework Statement In this circuit, find i(t), knowing that v_s= 2 \cos \left(w x+\frac{\pi }{2}\right), and that, at the source's frequency, X_C= -1 Ω and X_L = 1 Ω. Homework Equations Basic phasors and dividers equations. Z_C = jX_C Z_L = jX_L The Attempt at a Solution I used dividers...

Uhm.. What do you mean? It depends on which x you choose. The function express that sum, indeed.

Right Trapezium - Simple Problem Using Trigonometry Homework Statement http://img207.imageshack.us/img207/8510/imagejat.jpg ABCD is a right trapezium. CB = 3 = CD. P is a point of CB. The angle CDP is called x. I have to express the function f(x) = DP + CP and I have to find the interval in...

Okay, but how to solve cubic trigonometic equations? I think I can get a quadratic equation, in some way. We are studying them, indeed, and there is nothing about cubic trigonometric equations in my book.

Homework Statement I'm trying to solve two similar equations, but I can't go on. This is the first one http://img818.imageshack.us/img818/298/imageevsu.jpg This is the second one: http://img7.imageshack.us/img7/7812/imageowud.jpg Homework Equations The Attempt at a Solution...

I've found my mistake, now I get 3cos^2x-sin^2x-2cosx=0 and the solution is pi/5. Thank you very much for helping!

I've written this system of equations: http://img13.imageshack.us/img13/9355/imagenxvc.jpg But I get 3cos^2x+sin^2x-2cosx=0 and the solution of the poblem that the book gives me is ∏/5.

Homework Statement http://img23.imageshack.us/img23/9427/imageyakj.jpg AC+CB=24 The bisector = 8. Find angle DCB, i.e. x. Homework Equations The Law of sines, I think.The Attempt at a Solution

So http://img52.imageshack.us/img52/2426/imagewrzu.jpg But they have different factors, how can I factor out (sinx-cosx)?

Homework Statement http://img35.imageshack.us/img35/806/imagezxg.jpg Homework Equations The Attempt at a Solution http://img853.imageshack.us/img853/4035/imageyffi.jpg

The teacher dictated us that problem. However I've just asked my schoolmates and the teacher said the solution was wrong and the right one was 8454!

Yes, exactly.

Do you mean in the problem statement ( :smile: ) or in my attempt?

Homework Statement A 900 kg car goes up along an inclined road by 30 degrees characterized by an acceleration of 0.25 m/s^2. If friction coefficient is 0.5, find the magnitude of the force that moves the car. Solution: F = 12285.6 N Homework Equations The Attempt at a Solution...