Recent content by kristo

Homework Statement The part I'm having problems with is where the last two expressions in 4.13 are equated. Why is xtKx*equal to x*^tKx*? The Attempt at a Solution xtKx* is an inner product and due to symmetry is equal to x*^tKx, but wouldn't equating x to x* mean every <x,y> = <x,x> =...

Anyone?

Homework Statement For the determinant \left| \begin{array}{ccc} a_1 & a_2 & a_3 \\ b_1 & b_2 & b_3 \\ c_1 & c_2 & c_3 \end{array} \right| , b and c being the base of a parallelepiped why is the equation \vec b \cdot (a_1^{'}e_1 + a_2^{'} e_2 + a_3^{'} e_3) = 0 (same goes for vector c)...

Homework Statement Find the antiderivative of \frac{1}{\sin\alpha} Homework Equations The Attempt at a Solution Ugh, maybe it's just a temporary brainfreeze, but I have no idea how to go about it.

Thanks a lot, I got it now. I keep forgetting the inverse trig derivatives.

Homework Statement \frac{dy}{dx}= y^2 + 1 Homework Equations The Attempt at a Solution I have no idea how to go about it. I've never solved a differential equation of second degree before.

Homework Statement Mary Jane grows herbs in her attic. The relationship between her inputs and outputs is given by the production function is Q = 3(K*L)^0.5 , where Q is value added (value of gross output less cost of electricity, fertilizer, seed, and food for a guard dog), K is the value...

Homework Statement The original problem is this: ab^2*cos(2x)*(cos(x))^2 + ba^2*sin(2x)*(sin(x))^2 = 0 And some of the more "logical" forms I've got to are these:2[tan(x)]^3-2tan(x) = -b/a tan(2x)*(tan(x))^2=-b/a But I can't solve these equations so I'd like to ask for some help here.

Homework Statement A plane starts its descent from height y=h at x =-L to land at (0,0). Choose a, b, c, d so its landing path y=ax^3 + bx^2 + cx + d is smooth.With dx/dt=V=constant, find dy/dt and d2y/dt2 at x=0 and x =-L. (To keep d2y/dt2 small, a coast-to-coast plane starts down L>100...

Hey, thanks for your reply. I had another go at the 1st problem and I solved it, got the same answer as the book. I did differently than you, though, using the congruence theorem and some trig. http://xs.to/xs.php?h=xs114&d=07170&f=matenurk.png Oh and there's a tiny difference between mine and...

Homework Statement Find the blue colored surface area. 1 http://img338.imageshack.us/img338/1630/graph1zd7.png The radii of the circles are 3 cm and 1 cm. 2 Find the surface area of the rosette inside the equilateral triangle with side a. http://img87.imageshack.us/img87/2590/graph2dj9.png...

I'm supposed to simplify this, help please! \frac{a^4-b^4}{4a^2+4b^2}:(a+b) Sorry for posting in the wrong section, could someone move it?