Total # Posts: 33

Math
Nevermind. I figured it out

Math
Find an equation of the hyperbola with its center at the origin. vertices:(3,0)(-3,0) Foci (5,0)(-5,0) My answer was x^2/3 - y^2/22 = 1. I do not know how to find a.

Math
Test for symmetry with repsect to Q=pi/2, the polar axis, and the pole. r=16cos 3Q r=16cos(3pi/3 + 3h) = 16(cos3pi/2 3h- sin 3pi/2 sin h) cos 3pi/2 = 0 sin 3pi/2 = -1 Not symmetrical My teacher said that this was wrong!Why?

Math
Find the vertex, focus, and directrix of the parabola. x^2 - 2x + 8y + 9 = 0 x^2 - 2x +1 = -8y + 9+ 1 (x-1)^2 = -8(y-1.25) vertex:(1,1.25) focus:(1,-.75) directrix: y=3.25 My teacher said that I have sign errors. I do not know where I went wrong.

Math
The rectangular coordinates of a point are given. Find two sets of polar coordinates for the point for 0 is less than or equal to Q is less than 2pi. (-3,-3) My answers were (-3sqrt2, pi/4) and (pi/4, -3sqrt2). My teacher said that my answers have to be in quadrant 3. Is my ...

Math
My teacher said that I had sign errors. I do not see where I went wrong.

Math
Is this correct?

Math
Find the vertex, focus, and directrix of the parabola. x^2 - 2x + 8y + 9 = 0 x^2 - 2x +1 = -8y + 9+ 1 (x-1)^2 = -8(y-1.25) vertex:(1,1.25) focus:(1,-.75) directrix: y=3.25

Math
Find an equation of the parabola. vertex:(-1,2) focus:(-1,0) (x+1)^2 = 4p(y-2) (x+1)^2 = 0(y-2) (x+1)^2 = (y-2) Am I correct?

Math
Use a graphing utility to graph the function. Then use the trace or table feature to identify the limit. lim 5/x-2 x-->2 I know I posted this question before but I am still having a hard time doing this. I pressed the y= button and typed the normal equation in: 5/x-2. Is ...

Math
so the vertices would be (2, -1+sqrt5/2) (2, -1-sqrt5/2)?

Math
Find the center, vertices, foci, and eccentricity of the ellipse. 9x^2 + 4y^2 - 36x + 8y + 31 = 0 I know the center is (2,-1) For the vertices I had (3,-1)(1,-1) and the foci (3.8,-1)(.20,-1) and e = 1.80 but I think these are wrong.

Math
use Demoivre's Theorem to find the indicated power of the complex number. Express the result in standard form. (2+2i)^6 a=2 b=2 n=6 r=sqrt 2^2 + 2^2 = sqrt8 Q=7pi/4 (sqrt8)^6 = 512 512(cos 6/1 x 7pi/4) + i sin 6 x 7pi/4 512 (cos 21pi/2) + i sin (21pi/2) 512(cos pi/2) + i (...

Math
Would n be 14?

Math
Logs are stacked up in apile as shown in the figure. The top row has 15 logs and the bottom row has 21 logs. How many logs are in the stack? a1= 1+14=15 an= 7+14=21 s1=(n/2)(a1+an) (n/2)(15+21) = 18 How do I figure out the n?

Math
use Demoivre's Theorem to find the indicated power of the complex number. Express the result in standard form. (2+2i)^6 a=2 b=2 n=6 r=sqrt 2^2 + 2^2 = sqrt8 Q=7pi/4 (sqrt8)^6 = 512 512(cos 6/1 x 7pi/4) + i sin 6 x 7pi/4 512 (cos 21pi/2) + i sin (21pi/2) 512(cos pi/2) + i (...

Math
I am not sure what to change.

Math
Find the angle Q between the two vectors. u = 10i + 40j v = -3j+8k cos <10,40,0> <0,-3,8> / sqrt1700 sqrt73 cos(-120/sqrt1700 sqrt73) = .9072885394 arc cos (.9072885394) = 24.86 degrees. Is this correct?

Math
I have a TI-83 graphing calculator. How do you graph a polar equation on this calculator. Also how would I graph lim 5/x-2 x-->2 in order to find the limit?

Math
Find an equation of the ellipse with its center at the origin. center(0,0) foci(2,0)(-2,0) major axis=8 My answer is x^2/16 + y^2/15 = 1. Is this correct?

Math
Find the center, vertices, foci, and eccentricity of the ellipse. 9x^2 + 4y^2 - 36x + 8y + 31 = 0 My answer was: center=(2,1) v=(-2,10)(-2,-10) f=(-2,11)(-2,-11) e=11/3 Where did I make a mistake?

Math
Thank You

Math
Write an expression for the most apparent nth term of the sequence. Assume n begins with 1. 3,7,11,15,19 My answer was an= 3 +4n but this wrong.

Math
When trying to solve arctan(sqrt 567.2 / -459.6) my answer was -2.96. My teacher said that i handled the radical wrong. She said I have to square both numbers, then add them, and then find the square root. I am confused because you cannot take the square root of -459.6. Please...

Math
The rectangular coordinates of a point are given. Find two sets of polar coordinates for the point. (-3,-3)

Math
Determine whether f is continuous at x=c in the function. Use the 3 conditions of continuity to justify your answer. f(x) = x-1/x+1 c=-1 My answer is not continuous. Am I correct?

Math
Thank You!

Math
plot the point given in polar coordinates and find the corresponding rectangular coordinates for the point. (-1 , -3pi/4) I do not understand.

Math
I need to graph the polar equation 3 + 3cosQ and i need to create a table of values for r and Q. Could someone please explain how I would do this? Thank you!

Math
I need to give an example of a function with at least one removable and one non-removable discontinuity. I am not to sure how to do this. Please explain! Thanky you

Math
Thank You!!

Math
A painter working at 100 feet from the ground, drops his paint brush onto the street below. The function, s(t)=-16t^2+100, gives the height(in feet) of the paint brush as it falls to the ground. The velocity at time t=2 seconds is given by lim s(2)-s(t)/2-t t-->2 Evaluate ...

Math
A point in polar coordinates is given, Find the corresponding rectangular coordinates for the point. (r,Q) = (4, 3pi/2) I know that you are suppose to use x=r cos Q and y=sin Q but I do not know how to plug this in.